WorldWideScience

Sample records for maximum usable frequency

  1. Effect of Training Frequency on Maximum Expiratory Pressure

    Science.gov (United States)

    Anand, Supraja; El-Bashiti, Nour; Sapienza, Christine

    2012-01-01

    Purpose: To determine the effects of expiratory muscle strength training (EMST) frequency on maximum expiratory pressure (MEP). Method: We assigned 12 healthy participants to 2 groups of training frequency (3 days per week and 5 days per week). They completed a 4-week training program on an EMST trainer (Aspire Products, LLC). MEP was the primary…

  2. Gravitational Waves and the Maximum Spin Frequency of Neutron Stars

    NARCIS (Netherlands)

    Patruno, A.; Haskell, B.; D'Angelo, C.

    2012-01-01

    In this paper, we re-examine the idea that gravitational waves are required as a braking mechanism to explain the observed maximum spin frequency of neutron stars. We show that for millisecond X-ray pulsars, the existence of spin equilibrium as set by the disk/magnetosphere interaction is sufficient

  3. Maximum Entropy, Word-Frequency, Chinese Characters, and Multiple Meanings

    Science.gov (United States)

    Yan, Xiaoyong; Minnhagen, Petter

    2015-01-01

    The word-frequency distribution of a text written by an author is well accounted for by a maximum entropy distribution, the RGF (random group formation)-prediction. The RGF-distribution is completely determined by the a priori values of the total number of words in the text (M), the number of distinct words (N) and the number of repetitions of the most common word (kmax). It is here shown that this maximum entropy prediction also describes a text written in Chinese characters. In particular it is shown that although the same Chinese text written in words and Chinese characters have quite differently shaped distributions, they are nevertheless both well predicted by their respective three a priori characteristic values. It is pointed out that this is analogous to the change in the shape of the distribution when translating a given text to another language. Another consequence of the RGF-prediction is that taking a part of a long text will change the input parameters (M, N, kmax) and consequently also the shape of the frequency distribution. This is explicitly confirmed for texts written in Chinese characters. Since the RGF-prediction has no system-specific information beyond the three a priori values (M, N, kmax), any specific language characteristic has to be sought in systematic deviations from the RGF-prediction and the measured frequencies. One such systematic deviation is identified and, through a statistical information theoretical argument and an extended RGF-model, it is proposed that this deviation is caused by multiple meanings of Chinese characters. The effect is stronger for Chinese characters than for Chinese words. The relation between Zipf’s law, the Simon-model for texts and the present results are discussed. PMID:25955175

  4. A Web-Based Graphical Food Frequency Assessment System: Design, Development and Usability Metrics.

    Science.gov (United States)

    Franco, Rodrigo Zenun; Alawadhi, Balqees; Fallaize, Rosalind; Lovegrove, Julie A; Hwang, Faustina

    2017-05-08

    Food frequency questionnaires (FFQs) are well established in the nutrition field, but there remain important questions around how to develop online tools in a way that can facilitate wider uptake. Also, FFQ user acceptance and evaluation have not been investigated extensively. This paper presents a Web-based graphical food frequency assessment system that addresses challenges of reproducibility, scalability, mobile friendliness, security, and usability and also presents the utilization metrics and user feedback from a deployment study. The application design employs a single-page application Web architecture with back-end services (database, authentication, and authorization) provided by Google Firebase's free plan. Its design and responsiveness take advantage of the Bootstrap framework. The FFQ was deployed in Kuwait as part of the EatWellQ8 study during 2016. The EatWellQ8 FFQ contains 146 food items (including drinks). Participants were recruited in Kuwait without financial incentive. Completion time was based on browser timestamps and usability was measured using the System Usability Scale (SUS), scoring between 0 and 100. Products with a SUS higher than 70 are considered to be good. A total of 235 participants created accounts in the system, and 163 completed the FFQ. Of those 163 participants, 142 reported their gender (93 female, 49 male) and 144 reported their date of birth (mean age of 35 years, range from 18-65 years). The mean completion time for all FFQs (n=163), excluding periods of interruption, was 14.2 minutes (95% CI 13.3-15.1 minutes). Female participants (n=93) completed in 14.1 minutes (95% CI 12.9-15.3 minutes) and male participants (n=49) completed in 14.3 minutes (95% CI 12.6-15.9 minutes). Participants using laptops or desktops (n=69) completed the FFQ in an average of 13.9 minutes (95% CI 12.6-15.1 minutes) and participants using smartphones or tablets (n=91) completed in an average of 14.5 minutes (95% CI 13.2-15.8 minutes). The median SUS

  5. Geodesic acoustic eigenmode for tokamak equilibrium with maximum of local GAM frequency

    Energy Technology Data Exchange (ETDEWEB)

    Lakhin, V.P. [NRC “Kurchatov Institute”, Moscow (Russian Federation); Sorokina, E.A., E-mail: sorokina.ekaterina@gmail.com [NRC “Kurchatov Institute”, Moscow (Russian Federation); Peoples' Friendship University of Russia, Moscow (Russian Federation)

    2014-01-24

    The geodesic acoustic eigenmode for tokamak equilibrium with the maximum of local GAM frequency is found analytically in the frame of MHD model. The analysis is based on the asymptotic matching technique.

  6. Maximum-likelihood methods for array processing based on time-frequency distributions

    Science.gov (United States)

    Zhang, Yimin; Mu, Weifeng; Amin, Moeness G.

    1999-11-01

    This paper proposes a novel time-frequency maximum likelihood (t-f ML) method for direction-of-arrival (DOA) estimation for non- stationary signals, and compares this method with conventional maximum likelihood DOA estimation techniques. Time-frequency distributions localize the signal power in the time-frequency domain, and as such enhance the effective SNR, leading to improved DOA estimation. The localization of signals with different t-f signatures permits the division of the time-frequency domain into smaller regions, each contains fewer signals than those incident on the array. The reduction of the number of signals within different time-frequency regions not only reduces the required number of sensors, but also decreases the computational load in multi- dimensional optimizations. Compared to the recently proposed time- frequency MUSIC (t-f MUSIC), the proposed t-f ML method can be applied in coherent environments, without the need to perform any type of preprocessing that is subject to both array geometry and array aperture.

  7. Evaluating Annual Maximum and Partial Duration Series for Estimating Frequency of Small Magnitude Floods

    Directory of Open Access Journals (Sweden)

    Fazlul Karim

    2017-06-01

    Full Text Available Understanding the nature of frequent floods is important for characterising channel morphology, riparian and aquatic habitat, and informing river restoration efforts. This paper presents results from an analysis on frequency estimates of low magnitude floods using the annual maximum and partial series data compared to actual flood series. Five frequency distribution models were fitted to data from 24 gauging stations in the Great Barrier Reef (GBR lagoon catchments in north-eastern Australia. Based on the goodness of fit test, Generalised Extreme Value, Generalised Pareto and Log Pearson Type 3 models were used to estimate flood frequencies across the study region. Results suggest frequency estimates based on a partial series are better, compared to an annual series, for small to medium floods, while both methods produce similar results for large floods. Although both methods converge at a higher recurrence interval, the convergence recurrence interval varies between catchments. Results also suggest frequency estimates vary slightly between two or more partial series, depending on flood threshold, and the differences are large for the catchments that experience less frequent floods. While a partial series produces better frequency estimates, it can underestimate or overestimate the frequency if the flood threshold differs largely compared to bankfull discharge. These results have significant implications in calculating the dependency of floodplain ecosystems on the frequency of flooding and their subsequent management.

  8. The effect of electric field maximum on the Rabi flopping and generated higher frequency spectra

    International Nuclear Information System (INIS)

    Niu Yueping; Cui Ni; Xiang Yang; Li Ruxin; Gong Shangqing; Xu Zhizhan

    2008-01-01

    We investigate the effect of the electric field maximum on the Rabi flopping and the generated higher frequency spectra properties by solving Maxwell-Bloch equations without invoking any standard approximations. It is found that the maximum of the electric field will lead to carrier-wave Rabi flopping (CWRF) through reversion dynamics which will be more evident when the applied field enters the sub-one-cycle regime. Therefore, under the interaction of sub-one-cycle pulses, the Rabi flopping follows the transient electric field tightly through the oscillation and reversion dynamics, which is in contrast to the conventional envelope Rabi flopping. Complete or incomplete population inversion can be realized through the control of the carrier-envelope phase (CEP). Furthermore, the generated higher frequency spectra will be changed from distinct to continuous or irregular with the variation of the CEP. Our results demonstrate that due to the evident maximum behavior of the electric field, pulses with different CEP give rise to different CWRFs, and then different degree of interferences lead to different higher frequency spectral features.

  9. Frequency-Domain Maximum-Likelihood Estimation of High-Voltage Pulse Transformer Model Parameters

    CERN Document Server

    Aguglia, D; Martins, C.D.A.

    2014-01-01

    This paper presents an offline frequency-domain nonlinear and stochastic identification method for equivalent model parameter estimation of high-voltage pulse transformers. Such kinds of transformers are widely used in the pulsed-power domain, and the difficulty in deriving pulsed-power converter optimal control strategies is directly linked to the accuracy of the equivalent circuit parameters. These components require models which take into account electric fields energies represented by stray capacitance in the equivalent circuit. These capacitive elements must be accurately identified, since they greatly influence the general converter performances. A nonlinear frequency-based identification method, based on maximum-likelihood estimation, is presented, and a sensitivity analysis of the best experimental test to be considered is carried out. The procedure takes into account magnetic saturation and skin effects occurring in the windings during the frequency tests. The presented method is validated by experim...

  10. 2-Step Maximum Likelihood Channel Estimation for Multicode DS-CDMA with Frequency-Domain Equalization

    Science.gov (United States)

    Kojima, Yohei; Takeda, Kazuaki; Adachi, Fumiyuki

    Frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion can provide better downlink bit error rate (BER) performance of direct sequence code division multiple access (DS-CDMA) than the conventional rake combining in a frequency-selective fading channel. FDE requires accurate channel estimation. In this paper, we propose a new 2-step maximum likelihood channel estimation (MLCE) for DS-CDMA with FDE in a very slow frequency-selective fading environment. The 1st step uses the conventional pilot-assisted MMSE-CE and the 2nd step carries out the MLCE using decision feedback from the 1st step. The BER performance improvement achieved by 2-step MLCE over pilot assisted MMSE-CE is confirmed by computer simulation.

  11. Usability Constructs

    DEFF Research Database (Denmark)

    Hertzum, Morten; Clemmesen, Torkil; Hornbæk, Kasper Anders Søren

    2007-01-01

    Whereas research on usability predominantly employs universal definitions of the aspects that comprise usability, people experience their use of information systems through personal constructs. Based on 48 repertory-grid interviews, this study investigates how such personal constructs are affected...... use of constructs traditionally associated with usability (e.g., easy-to-use, intuitive, and liked). Further analysis of the data is ongoing...

  12. High-frequency maximum observable shaking map of Italy from fault sources

    KAUST Repository

    Zonno, Gaetano; Basili, Roberto; Meroni, Fabrizio; Musacchio, Gemma; Mai, Paul Martin; Valensise, Gianluca

    2012-01-01

    We present a strategy for obtaining fault-based maximum observable shaking (MOS) maps, which represent an innovative concept for assessing deterministic seismic ground motion at a regional scale. Our approach uses the fault sources supplied for Italy by the Database of Individual Seismogenic Sources, and particularly by its composite seismogenic sources (CSS), a spatially continuous simplified 3-D representation of a fault system. For each CSS, we consider the associated Typical Fault, i. e., the portion of the corresponding CSS that can generate the maximum credible earthquake. We then compute the high-frequency (1-50 Hz) ground shaking for a rupture model derived from its associated maximum credible earthquake. As the Typical Fault floats within its CSS to occupy all possible positions of the rupture, the high-frequency shaking is updated in the area surrounding the fault, and the maximum from that scenario is extracted and displayed on a map. The final high-frequency MOS map of Italy is then obtained by merging 8,859 individual scenario-simulations, from which the ground shaking parameters have been extracted. To explore the internal consistency of our calculations and validate the results of the procedure we compare our results (1) with predictions based on the Next Generation Attenuation ground-motion equations for an earthquake of M w 7.1, (2) with the predictions of the official Italian seismic hazard map, and (3) with macroseismic intensities included in the DBMI04 Italian database. We then examine the uncertainties and analyse the variability of ground motion for different fault geometries and slip distributions. © 2012 Springer Science+Business Media B.V.

  13. High-frequency maximum observable shaking map of Italy from fault sources

    KAUST Repository

    Zonno, Gaetano

    2012-03-17

    We present a strategy for obtaining fault-based maximum observable shaking (MOS) maps, which represent an innovative concept for assessing deterministic seismic ground motion at a regional scale. Our approach uses the fault sources supplied for Italy by the Database of Individual Seismogenic Sources, and particularly by its composite seismogenic sources (CSS), a spatially continuous simplified 3-D representation of a fault system. For each CSS, we consider the associated Typical Fault, i. e., the portion of the corresponding CSS that can generate the maximum credible earthquake. We then compute the high-frequency (1-50 Hz) ground shaking for a rupture model derived from its associated maximum credible earthquake. As the Typical Fault floats within its CSS to occupy all possible positions of the rupture, the high-frequency shaking is updated in the area surrounding the fault, and the maximum from that scenario is extracted and displayed on a map. The final high-frequency MOS map of Italy is then obtained by merging 8,859 individual scenario-simulations, from which the ground shaking parameters have been extracted. To explore the internal consistency of our calculations and validate the results of the procedure we compare our results (1) with predictions based on the Next Generation Attenuation ground-motion equations for an earthquake of M w 7.1, (2) with the predictions of the official Italian seismic hazard map, and (3) with macroseismic intensities included in the DBMI04 Italian database. We then examine the uncertainties and analyse the variability of ground motion for different fault geometries and slip distributions. © 2012 Springer Science+Business Media B.V.

  14. [Polish guidelines of 2001 for maximum admissible intensities in high frequency EMF versus European Union recommendations].

    Science.gov (United States)

    Aniołczyk, Halina

    2003-01-01

    In 1999, a draft of amendments to maximum admissible intensities (MAI) of electromagnetic fields (0 Hz-300 GHz) was prepared by Professor H. Korniewicz of the Central Institute for Labour Protection, Warsaw, in cooperation with the Nofer Institute of Occupational Medicine, Łódź (radio- and microwaves) and the Military Institute of Hygiene and Epidemiology, Warsaw (pulse radiation). Before 2000, the development of the national MAI guidelines for the frequency range of 0.1 MHz-300 GHz was based on the knowledge of biological and health effects of EMF exposure available on the turn of the 1960s. A current basis for establishing the MAI international standards is a well-documented thermal effect measured by the value of a specific absorption rate (SAR), whereas the effects of resonant absorption imposes the nature of the functional dependency on EMF frequency. The Russian standards, already thoroughly analyzed, still take so-called non-thermal effects and the conception of energetic load for a work-shift with its progressive averaging (see hazardous zone in Polish guidelines) as a basis for setting maximum admissible intensities. The World Health Organization recommends a harmonization of the EMF protection guidelines, existing in different countries, with the guidelines of the International Commission for Non-Ionizing Radiation Protection (ICNIRP), and its position is supported by the European Union.

  15. Photovoltaic High-Frequency Pulse Charger for Lead-Acid Battery under Maximum Power Point Tracking

    Directory of Open Access Journals (Sweden)

    Hung-I. Hsieh

    2013-01-01

    Full Text Available A photovoltaic pulse charger (PV-PC using high-frequency pulse train for charging lead-acid battery (LAB is proposed not only to explore the charging behavior with maximum power point tracking (MPPT but also to delay sulfating crystallization on the electrode pores of the LAB to prolong the battery life, which is achieved due to a brief pulse break between adjacent pulses that refreshes the discharging of LAB. Maximum energy transfer between the PV module and a boost current converter (BCC is modeled to maximize the charging energy for LAB under different solar insolation. A duty control, guided by a power-increment-aided incremental-conductance MPPT (PI-INC MPPT, is implemented to the BCC that operates at maximum power point (MPP against the random insolation. A 250 W PV-PC system for charging a four-in-series LAB (48 Vdc is examined. The charging behavior of the PV-PC system in comparison with that of CC-CV charger is studied. Four scenarios of charging statuses of PV-BC system under different solar insolation changes are investigated and compared with that using INC MPPT.

  16. Global usability

    CERN Document Server

    Douglas, Ian

    2011-01-01

    The concept of usability has become an increasingly important consideration in the design of all kinds of technology. As more products are aimed at global markets and developed through internationally distributed teams, usability design needs to be addressed in global terms. Interest in usability as a design issue and specialist area of research and education has developed steadily in North America and Europe since the 1980's. However, it is only over the last ten years that it has emerged as a global concern. Global Usability provides an introduction to the important issues in globalizing des

  17. Cultural Usability

    DEFF Research Database (Denmark)

    Shi, Qingxin

    2007-01-01

    Culture has already played an important role in the global market. It not only affects products, but also impacts on usability evaluation methods. This project aims to examine in the established thinking aloud usability evaluation method (TA UEM), how does the evaluator build a supportive...

  18. Evaluating Usability

    DEFF Research Database (Denmark)

    Nørgaard, Mie; Høegh, Rune T.

    2008-01-01

    Usability evaluation is widely accepted as a valuable activity in software development. However, how results effectively are fed back to developers is still a relatively unexplored area. We argue that usability feedback can be understood as an argument for a series of usability problems......, and that basic concepts from argumentation theory can help us understand how to create persuasive feedback. We revisit two field studies on usability feedback to study if concepts from Toulmin's model for argumentation and Aristotle's modes of persuasion can explain why some feedback formats outperform others....... We recommend that evaluators specifically back up the warrants behind their usability claims, that their arguments use several modes of persuasion, and that they present feedback in browsable amounts not to overwhelm developers with information. For complex and controversial problems, we advise...

  19. Radio Frequency Transistors Using Aligned Semiconducting Carbon Nanotubes with Current-Gain Cutoff Frequency and Maximum Oscillation Frequency Simultaneously Greater than 70 GHz.

    Science.gov (United States)

    Cao, Yu; Brady, Gerald J; Gui, Hui; Rutherglen, Chris; Arnold, Michael S; Zhou, Chongwu

    2016-07-26

    In this paper, we report record radio frequency (RF) performance of carbon nanotube transistors based on combined use of a self-aligned T-shape gate structure, and well-aligned, high-semiconducting-purity, high-density polyfluorene-sorted semiconducting carbon nanotubes, which were deposited using dose-controlled, floating evaporative self-assembly method. These transistors show outstanding direct current (DC) performance with on-current density of 350 μA/μm, transconductance as high as 310 μS/μm, and superior current saturation with normalized output resistance greater than 100 kΩ·μm. These transistors create a record as carbon nanotube RF transistors that demonstrate both the current-gain cutoff frequency (ft) and the maximum oscillation frequency (fmax) greater than 70 GHz. Furthermore, these transistors exhibit good linearity performance with 1 dB gain compression point (P1dB) of 14 dBm and input third-order intercept point (IIP3) of 22 dBm. Our study advances state-of-the-art of carbon nanotube RF electronics, which have the potential to be made flexible and may find broad applications for signal amplification, wireless communication, and wearable/flexible electronics.

  20. Mobile Usability

    DEFF Research Database (Denmark)

    Aryana, Bijan; Clemmensen, Torkil

    2013-01-01

    In this article, a country specific comparative mobile usability study is presented, using Iran and Turkey as the two chosen emerging/emergent nation exemplars of smartphone usage and adoption. In a focus group study, three mobile applications were selected by first-time users of smartphones...... personal contacts. The results and analysis establish the existence of country specific issues and concerns, as well as reveal generic usability issues. The article concludes that the source of these issues is most likely due to a combination of certain contextual features endemic to both Iran and Turkey...

  1. Direct comparison of phase-sensitive vibrational sum frequency generation with maximum entropy method: case study of water.

    Science.gov (United States)

    de Beer, Alex G F; Samson, Jean-Sebastièn; Hua, Wei; Huang, Zishuai; Chen, Xiangke; Allen, Heather C; Roke, Sylvie

    2011-12-14

    We present a direct comparison of phase sensitive sum-frequency generation experiments with phase reconstruction obtained by the maximum entropy method. We show that both methods lead to the same complex spectrum. Furthermore, we discuss the strengths and weaknesses of each of these methods, analyzing possible sources of experimental and analytical errors. A simulation program for maximum entropy phase reconstruction is available at: http://lbp.epfl.ch/. © 2011 American Institute of Physics

  2. A New High Frequency Injection Method Based on Duty Cycle Shifting without Maximum Voltage Magnitude Loss

    DEFF Research Database (Denmark)

    Wang, Dong; Lu, Kaiyuan; Rasmussen, Peter Omand

    2015-01-01

    The conventional high frequency signal injection method is to superimpose a high frequency voltage signal to the commanded stator voltage before space vector modulation. Therefore, the magnitude of the voltage used for machine torque production is limited. In this paper, a new high frequency...... amplitude. This may be utilized to develop new position estimation algorithm without involving the inductance in the medium to high speed range. As an application example, a developed inductance independent position estimation algorithm using the proposed high frequency injection method is applied to drive...... injection method, in which high frequency signal is generated by shifting the duty cycle between two neighboring switching periods, is proposed. This method allows injecting a high frequency signal at half of the switching frequency without the necessity to sacrifice the machine fundamental voltage...

  3. Measures of maximum magnetic field in 3 GHz radio frequency superconducting cavities; Mesures du gradient accelerateur maximum dans des cavites supraconductrices en regime impulsionnel a 3 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Catherine [Paris-11 Univ., 91 Orsay (France)

    2000-01-19

    Theoretical models have shown that the maximum magnetic field in radio frequency superconducting cavities is the superheating field H{sub sh}. For niobium, H{sub sh} is 25 - 30% higher than the thermodynamical H{sub c} field: H{sub sh} within (240 - 274) mT. However, the maximum magnetic field observed so far is in the range H{sub c,max} = 152 mT for the best 1.3 GHz Nb cavities. This field is lower than the critical field H{sub c1} above which the superconductor breaks up into divided normal and superconducting zones (H{sub c1}{<=}H{sub c}). Thermal instabilities are responsible for this low value. In order to reach H{sub sh} before thermal breakdown, high power short pulses are used. The cavity needs then to be strongly over-coupled. The dedicated test bed has been built from the collaboration between Istituto Nazionale di Fisica Nucleare (INFN) - Sezione di Genoa, and the Service d'Etudes et Realisation d'Accelerateurs (SERA) of Laboratoire de l'Accelerateur Lineaire (LAL). The maximum magnetic field, H{sub rf,max}, measurements on INFN cavities give lower results than the theoretical speculations and are in agreement with previous results. The superheating magnetic fields is linked to the magnetic penetration depth. This superconducting characteristic length can be used to determine the quality of niobium through the ratio between the resistivity measured at 300 K and 4.2 K in the normal conducting state (RRR). Results have been compared to previous ones and agree pretty well. They show that the RRR measured on cavities is superficial and lower than the RRR measured on samples which concerns the volume. (author)

  4. Towards a frequency-dependent discrete maximum principle for the implicit Monte Carlo equations

    Energy Technology Data Exchange (ETDEWEB)

    Wollaber, Allan B [Los Alamos National Laboratory; Larsen, Edward W [Los Alamos National Laboratory; Densmore, Jeffery D [Los Alamos National Laboratory

    2010-12-15

    It has long been known that temperature solutions of the Implicit Monte Carlo (IMC) equations can exceed the external boundary temperatures, a so-called violation of the 'maximum principle.' Previous attempts at prescribing a maximum value of the time-step size {Delta}{sub t} that is sufficient to eliminate these violations have recommended a {Delta}{sub t} that is typically too small to be used in practice and that appeared to be much too conservative when compared to numerical solutions of the IMC equations for practical problems. In this paper, we derive a new estimator for the maximum time-step size that includes the spatial-grid size {Delta}{sub x}. This explicitly demonstrates that the effect of coarsening {Delta}{sub x} is to reduce the limitation on {Delta}{sub t}, which helps explain the overly conservative nature of the earlier, grid-independent results. We demonstrate that our new time-step restriction is a much more accurate means of predicting violations of the maximum principle. We discuss how the implications of the new, grid-dependent timestep restriction can impact IMC solution algorithms.

  5. Towards a frequency-dependent discrete maximum principle for the implicit Monte Carlo equations

    International Nuclear Information System (INIS)

    Wollaber, Allan B.; Larsen, Edward W.; Densmore, Jeffery D.

    2011-01-01

    It has long been known that temperature solutions of the Implicit Monte Carlo (IMC) equations can exceed the external boundary temperatures, a so-called violation of the 'maximum principle'. Previous attempts at prescribing a maximum value of the time-step size Δ t that is sufficient to eliminate these violations have recommended a Δ t that is typically too small to be used in practice and that appeared to be much too conservative when compared to numerical solutions of the IMC equations for practical problems. In this paper, we derive a new estimator for the maximum time-step size that includes the spatial-grid size Δ x . This explicitly demonstrates that the effect of coarsening Δ x is to reduce the limitation on Δ t , which helps explain the overly conservative nature of the earlier, grid-independent results. We demonstrate that our new time-step restriction is a much more accurate means of predicting violations of the maximum principle. We discuss how the implications of the new, grid-dependent time-step restriction can impact IMC solution algorithms. (author)

  6. Images of Usability

    DEFF Research Database (Denmark)

    Hertzum, Morten

    2010-01-01

    unless confronted with alternative images. This study delineates six images of usability: universal usability, situational usability, perceived usability, hedonic usability, organizational usability, and cultural usability. The different foci of the images provide opportunities for becoming sensitized...... assume different images of usability and a need for supplementary methods addressing the collaborative and long-term aspects of usability. Moreover, the images call for extending the scope of practical usability work to include the effects achieved by users during their use of systems for real work....

  7. Maximum power gains of radio-frequency-driven two-energy-component tokamak reactors

    International Nuclear Information System (INIS)

    Jassby, D.L.

    1974-11-01

    Two-energy-component fusion reactors in which the suprathermal component (D) is produced by harmonic cyclotron ''runaway'' of resonant ions are considered. In one ideal case, the fast hydromagnetic wave at ω = 2ω/sub cD/ produces an energy distribution f(W) approximately constant (up to W/sub max/) that includes all deuterons, which then thermalize and react with the cold tritons. In another ideal case, f(W) approximately constant is maintained by the fast wave at ω = ω/sub cD/. If one neglects (1) direct rf input to the bulk-plasma electrons and tritons, and (2) the fact that many deuterons are not resonantly accelerated, then the maximum ideal power gain is about 0.85 Q/sub m/ in the first case and 1.05 Q/sub m/ in the second case, where Q/sub m/ is the maximum fusion gain in the beam-injection scheme (e.g., Q/sub m/ = 1.9 at T/sub e/ = 10 keV). Because of nonideal effects, the cyclotron runaway phenomenon may find its most practical use in the heating of 50:50 D--T plasmas to ignition. (auth)

  8. Examination into the maximum rotational frequency for an in-plane switched active waveplate device

    International Nuclear Information System (INIS)

    Davidson, A J; Elston, S J; Raynes, E P

    2005-01-01

    An examination of an active waveplate device using a one-dimensional model, giving numerical and analytical results, is presented. The model calculates the director and twist configuration by minimizing the free energy of the system with simple homeotropic boundary conditions. The effect of varying the in-plane electric field in both magnitude and direction is examined, and it is shown that the twist through the cell is constant in time as the field is rotated. As the electric field is rotated, the director field lags behind by an angle which increases as the frequency of the electric field rotation increases. When this angle reaches approximately π/4 the director field no longer follows the electric field in a uniform way. Using mathematical analysis it is shown that the conditions on which the director profile will fail to follow the rotating electric field depend on the frequency of electric field rotation, the magnitude of the electric field, the dielectric anisotropy and the viscosity of the liquid crystal

  9. Effects of different strength training frequencies on maximum strength, body composition and functional capacity in healthy older individuals.

    Science.gov (United States)

    Turpela, Mari; Häkkinen, Keijo; Haff, Guy Gregory; Walker, Simon

    2017-11-01

    There is controversy in the literature regarding the dose-response relationship of strength training in healthy older participants. The present study determined training frequency effects on maximum strength, muscle mass and functional capacity over 6months following an initial 3-month preparatory strength training period. One-hundred and six 64-75year old volunteers were randomly assigned to one of four groups; performing strength training one (EX1), two (EX2), or three (EX3) times per week and a non-training control (CON) group. Whole-body strength training was performed using 2-5 sets and 4-12 repetitions per exercise and 7-9 exercises per session. Before and after the intervention, maximum dynamic leg press (1-RM) and isometric knee extensor and plantarflexor strength, body composition and quadriceps cross-sectional area, as well as functional capacity (maximum 7.5m forward and backward walking speed, timed-up-and-go test, loaded 10-stair climb test) were measured. All experimental groups increased leg press 1-RM more than CON (EX1: 3±8%, EX2: 6±6%, EX3: 10±8%, CON: -3±6%, Ptraining frequency would induce greater benefit to maximum walking speed (i.e. functional capacity) despite a clear dose-response in dynamic 1-RM strength, at least when predominantly using machine weight-training. It appears that beneficial functional capacity improvements can be achieved through low frequency training (i.e. 1-2 times per week) in previously untrained healthy older participants. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. How do Usability Professionals Construe Usability?

    DEFF Research Database (Denmark)

    Hertzum, Morten; Clemmensen, Torkil

    2012-01-01

    distinguishing it from user experience. On the basis of repertory-grid interviews with 24 Chinese, Danish, and Indian usability professionals we find that they make use of more utilitarian than experiential, i.e. user-experience related, constructs. This indicates that goal-related performance is central......’ constructs, particularly their experiential constructs, go considerably beyond ISO 9241 usability, indicating a discrepancy between this definition of usability and the thinking of the professionals concerned with delivering usability. Finally, usability is construed rather similarly across the three...

  11. Sample size in usability studies

    NARCIS (Netherlands)

    Schmettow, Martin

    2012-01-01

    Usability studies are important for developing usable, enjoyable products, identifying design flaws (usability problems) likely to compromise the user experience. Usability testing is recommended for improving interactive design, but discovery of usability problems depends on the number of users

  12. Evaluation of maximum voided volume in Korean children by use of a 48-h frequency volume chart.

    Science.gov (United States)

    Kim, Sun-Ouck; Kim, Kyung Do; Kim, Young Sig; Kim, Jun Mo; Moon, Du Geon; Park, Sungchan; Lee, Sang Don; Chung, Jae Min; Cho, Won Yeol

    2012-08-01

    Study Type - Diagnostic (validating cohort). Level of Evidence 2a. What's known on the subject? and What does the study add? The relationship between the maximum voided volume followed a linear curve. The formula presented, bladder capacity (mL) = 12 ×[age (years) + 11], is thought to be a reasonable one for Korean children. Korean children have a smaller bladder capacity than that reported in previous Western studies. • To develop practical guidelines for the prediction of normal bladder capacity in Korean children measured by a frequency volume chart (FVC), maximum voided volume (MVV) is an important factor in the diagnosis of children with abnormal voiding function. • In all, 298 children, aged 3-13 years, with no history of voiding disorders volunteered for the study. The MVV was determined in 219 subjects by use of a completely recorded FVC. • Linear regression analysis was used to define the exact relationship between age and bladder capacity. An approximate formula related age to bladder capacity as follows: bladder capacity (mL) = 12 ×[age (years) + 11]. • The relationship between the MVV measured by a FVC by age (3-13 years) of Korean children followed a linear curve. • When applied to normal voiding patterns, the formula presented appears to be a reasonable one for Korean children. © 2011 BJU INTERNATIONAL.

  13. Usability and User Experience Information in Reviews

    DEFF Research Database (Denmark)

    Hedegaard, Steffen

    future versions of the prod- uct? The results show that users write about product use in terms related to standard and popularly researched aspects of usability and user experience, e.g. effiiency, effectiveness, enjoyment, frustration. The frequency with which different aspects are depicted in reviews...... differs significantly between product domains. We also find that reviews contain descriptions of more persistent usability issues. I devise automatic methods for classifying sentences with regard to dimensions of both usability and user experience and usability problems and perform a linguistic analysis...

  14. A Comparative Frequency Analysis of Maximum Daily Rainfall for a SE Asian Region under Current and Future Climate Conditions

    Directory of Open Access Journals (Sweden)

    Velautham Daksiya

    2017-01-01

    Full Text Available The impact of changing climate on the frequency of daily rainfall extremes in Jakarta, Indonesia, is analysed and quantified. The study used three different models to assess the changes in rainfall characteristics. The first method involves the use of the weather generator LARS-WG to quantify changes between historical and future daily rainfall maxima. The second approach consists of statistically downscaling general circulation model (GCM output based on historical empirical relationships between GCM output and station rainfall. Lastly, the study employed recent statistically downscaled global gridded rainfall projections to characterize climate change impact rainfall structure. Both annual and seasonal rainfall extremes are studied. The results show significant changes in annual maximum daily rainfall, with an average increase as high as 20% in the 100-year return period daily rainfall. The uncertainty arising from the use of different GCMs was found to be much larger than the uncertainty from the emission scenarios. Furthermore, the annual and wet seasonal analyses exhibit similar behaviors with increased future rainfall, but the dry season is not consistent across the models. The GCM uncertainty is larger in the dry season compared to annual and wet season.

  15. Marketing through Usability.

    Science.gov (United States)

    Morgan, Eric Lease

    1999-01-01

    Suggests that one of the best ways to get word-of-mouth marketing of library technology is to provide "usable" products and services. Provides an international standards definition on usability and notes that understanding usability combines an understanding of user needs/wants with an understanding of goals, functions, and limitations…

  16. Usability testing for dummies

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Usability testing seems complicated and time-consuming. Is it though? In fact, it is the best way to understand how real users experience your product. In this interactive session, we will do a live usability test and you will get advice on how to conduct your own usability tests.

  17. Exploring Multiple Usability Perspectives

    DEFF Research Database (Denmark)

    Uldall-Espersen, Tobias

    2007-01-01

    Industrial usability work often fails to produce the expected impact on software products even though significant resources have been used on uncovering problems and suggesting improvements. So, it seems that feedback from industrial usability work lacks persuasiveness, i.e. it fails to convince...... the key stakeholders that actions need to be taken. This study reports from interviews with 26 stakeholders in software development projects. Our data suggests that the interviewees address usability using different perspectives and based on our observations we describe five such perspectives. Further, we...... discuss how applying different usability perspectives might inform the persuasiveness of usability work....

  18. Measurement of the Maximum Frequency of Electroglottographic Fluctuations in the Expiration Phase of Volitional Cough as a Functional Test for Cough Efficiency.

    Science.gov (United States)

    Iwahashi, Toshihiko; Ogawa, Makoto; Hosokawa, Kiyohito; Kato, Chieri; Inohara, Hidenori

    2017-10-01

    The hypotheses of the present study were that the maximum frequency of fluctuation of electroglottographic (EGG) signals in the expiration phase of volitional cough (VC) reflects the cough efficiency and that this EGG parameter is affected by impaired laryngeal closure, expiratory effort strength, and gender. For 20 normal healthy adults and 20 patients diagnosed with unilateral vocal fold paralysis (UVFP), each participant was fitted with EGG electrodes on the neck, had a transnasal laryngo-fiberscope inserted, and was asked to perform weak/strong VC tasks while EGG signals and a high-speed digital image of the larynx were recorded. The maximum frequency was calculated in the EGG fluctuation region coinciding with vigorous vocal fold vibration in the laryngeal HSDIs. In addition, each participant underwent spirometry for measurement of three aerodynamic parameters, including peak expiratory air flow (PEAF), during weak/strong VC tasks. Significant differences were found for both maximum EGG frequency and PEAF between the healthy and UVFP groups and between the weak and strong VC tasks. Among the three cough aerodynamic parameters, PEAF showed the highest positive correlation with the maximum EGG frequency. The correlation coefficients between the maximum EGG frequency and PEAF recorded simultaneously were 0.574 for the whole group, and 0.782/0.717/0.823/0.688 for the male/female/male-healthy/male-UVFP subgroups, respectively. Consequently, the maximum EGG frequency measured in the expiration phase of VC was shown to reflect the velocity of expiratory airflow to some extent and was suggested to be affected by vocal fold physical properties, glottal closure condition, and the expiratory function.

  19. Maximum generation power evaluation of variable frequency offshore wind farms when connected to a single power converter

    Energy Technology Data Exchange (ETDEWEB)

    Gomis-Bellmunt, Oriol; Sumper, Andreas [Centre d' Innovacio Tecnologica en Convertidors Estatics i Accionaments (CITCEA-UPC), Universitat Politecnica de Catalunya UPC, Av. Diagonal, 647, Pl. 2, 08028 Barcelona (Spain); IREC Catalonia Institute for Energy Research, Barcelona (Spain); Junyent-Ferre, Adria; Galceran-Arellano, Samuel [Centre d' Innovacio Tecnologica en Convertidors Estatics i Accionaments (CITCEA-UPC), Universitat Politecnica de Catalunya UPC, Av. Diagonal, 647, Pl. 2, 08028 Barcelona (Spain)

    2010-10-15

    The paper deals with the evaluation of power generated by variable and constant frequency offshore wind farms connected to a single large power converter. A methodology to analyze different wind speed scenarios and system electrical frequencies is presented and applied to a case study, where it is shown that the variable frequency wind farm concept (VF) with a single power converter obtains 92% of the total available power, obtained with individual power converters in each wind turbine (PC). The PC scheme needs multiple power converters implying drawbacks in terms of cost, maintenance and reliability. The VF scheme is also compared to a constant frequency scheme CF, and it is shown that a significant power increase of more than 20% can be obtained with VF. The case study considers a wind farm composed of four wind turbines based on synchronous generators. (author)

  20. Evaluating Web Usability

    Science.gov (United States)

    Snider, Jean; Martin, Florence

    2012-01-01

    Web usability focuses on design elements and processes that make web pages easy to use. A website for college students was evaluated for underutilization. One-on-one testing, focus groups, web analytics, peer university review and marketing focus group and demographic data were utilized to conduct usability evaluation. The results indicated that…

  1. Personal Usability Constructs

    DEFF Research Database (Denmark)

    Hertzum, Morten; Clemmensen, Torkil; Hornbæk, Kasper

    2011-01-01

    Whereas the concept of usability is predominantly defined analytically, people relate to systems through personal usability constructs. Based on 48 repertory-grid interviews, this study investigates how such personal constructs are affected by two factors crucial to the international development...

  2. Cross cultural usability testing

    DEFF Research Database (Denmark)

    Clemmensen, Torkil; Goyal, Shivam

    2005-01-01

    In this paper, we present the results of a pilot study in Denmark of cross cultural effects on Think Aloud usability testing. We provide an overview of previous research on cross cultural usability evaluation with a special focus on the relationship between the evaluator and the test user....... This relation was studied in an experiment with usability testing of a localized clipart application in which eight participants from Denmark and India formed pairs of evaluator-test user. The test users were asked to think aloud and the evaluators' role were to facilitate the test users thinking aloud...... and hereby identify usability problems with the clipart application. Data on the evaluators' and test users' behaviour were recorded and analyzed by coding and summarizing statistics on these behavioural events. The results show that Think Aloud Usability Test of a localized application is most effectively...

  3. Critical frequency and maximum electron density of F2 region over four stations in the North American sector

    Czech Academy of Sciences Publication Activity Database

    Ezquer, R. G.; Cabrera, M. A.; López, J. L.; Albornoz, M. R.; Mosert, M.; Marcó, P.; Burešová, Dalia

    2011-01-01

    Roč. 73, č. 4 (2011), s. 420-429 ISSN 1364-6826 Institutional research plan: CEZ:AV0Z30420517 Keywords : Ionosphere * F2 region * Critical frequency * Electron density * Model Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.596, year: 2011 http://www.sciencedirect.com/science/article/pii/S1364682610002786

  4. Expected usability is not a valid indicator of experienced usability

    Directory of Open Access Journals (Sweden)

    Meinald T. Thielsch

    2015-09-01

    Full Text Available Usability is a core construct of website evaluation and inherently defined as interactive. Yet, when analysing first impressions of websites, expected usability, i.e., before use, is of interest. Here we investigate to what extend ratings of expected usability are related to (a experienced usability, i.e., ratings after use, and (b objective usability measures, i.e., task performance. Furthermore, we try to elucidate how ratings of expected usability are correlated to aesthetic judgments. In an experiment, 57 participants submitted expected usability ratings after the presentation of website screenshots in three viewing-time conditions (50, 500, and 10,000 ms and after an interactive task (experienced usability. Additionally, objective usability measures (task completion and duration and subjective aesthetics evaluations were recorded for each website. The results at both the group and individual level show that expected usability ratings are not significantly related either to experienced usability or objective usability measures. Instead, they are highly correlated with aesthetics ratings. Taken together, our results highlight the need for interaction in empirical website usability testing, even when exploring very early usability impressions. In our study, user ratings of expected usability were no valid proxy neither for objective usability nor for experienced website usability.

  5. Analysis in usability evaluations

    DEFF Research Database (Denmark)

    Følstad, Asbjørn; Lai-Chong Law, Effie; Hornbæk, Kasper

    2010-01-01

    While the planning and implementation of usability evaluations are well described in the literature, the analysis of the evaluation data is not. We present interviews with 11 usability professionals on how they conduct analysis, describing the resources, collaboration, creation of recommendations......, and prioritization involved. The interviews indicate a lack of structure in the analysis process and suggest activities, such as generating recommendations, that are unsupported by existing methods. We discuss how to better support analysis, and propose four themes for future research on analysis in usability...

  6. Usability in Scientific Databases

    Directory of Open Access Journals (Sweden)

    Ana-Maria Suduc

    2012-07-01

    Full Text Available Usability, most often defined as the ease of use and acceptability of a system, affects the users' performance and their job satisfaction when working with a machine. Therefore, usability is a very important aspect which must be considered in the process of a system development. The paper presents several numerical data related to the history of the scientific research of the usability of information systems, as it is viewed in the information provided by three important scientific databases, Science Direct, ACM Digital Library and IEEE Xplore Digital Library, at different queries related to this field.

  7. Distributed usability evaluation

    DEFF Research Database (Denmark)

    Christensen, Lars; Frøkjær, Erik

    2010-01-01

    We present DUE (Distributed Usability Evaluation), a technique for collecting and evaluating usability data. The DUE infrastructure involves a client-server network. A client-based tool resides on the workstation of each user, providing a screen video recording, microphone input of voice commentary......, and a window for a severity rating. The idea is for the user to work naturalistically, clicking a button when a usability problem or point of uncertainty is encountered, to describe it verbally along with illustrating it on screen, and to rate its severity. These incidents are accumulated on a server......, providing access to an evaluator (usability expert) and to product developers or managers who want to review the incidents and analyse them. DUE supports evaluation in the development stages from running prototypes and onwards. A case study of the use of DUE in a corporate environment is presented...

  8. Gate-Recessed AlGaN/GaN MOSHEMTs with the Maximum Oscillation Frequency Exceeding 120 GHz on Sapphire Substrates

    International Nuclear Information System (INIS)

    Kong Xin; Wei Ke; Liu Guo-Guo; Liu Xin-Yu

    2012-01-01

    Gate-recessed AlGaN/GaN metal-oxide-semiconductor high electron mobility transistors (MOSHEMTs) on sapphire substrates are fabricated. The devices with a gate length of 160 nm and a gate periphery of 2 × 75 μm exhibit two orders of magnitude reduction in gate leakage current and enhanced off-state breakdown characteristics, compared with conventional HEMTs. Furthermore, the extrinsic transconductance of an MOSHEMT is 237.2 mS/mm, only 7% lower than that of Schottky-gate HEMT. An extrinsic current gain cutoff frequency f T of 65 GHz and a maximum oscillation frequency f max of 123 GHz are deduced from rf small signal measurements. The high f max demonstrates that gate-recessed MOSHEMTs are of great potential in millimeter wave frequencies. (cross-disciplinary physics and related areas of science and technology)

  9. Full on-chip and area-efficient CMOS LDO with zero to maximum load stability using adaptive frequency compensation

    Energy Technology Data Exchange (ETDEWEB)

    Ma Haifeng; Zhou Feng, E-mail: fengzhou@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

    2010-01-15

    A full on-chip and area-efficient low-dropout linear regulator (LDO) is presented. By using the proposed adaptive frequency compensation (AFC) technique, full on-chip integration is achieved without compromising the LDO's stability in the full output current range. Meanwhile, the use of a compact pass transistor (the compact pass transistor serves as the gain fast roll-off output stage in the AFC technique) has enabled the LDO to be very area-efficient. The proposed LDO is implemented in standard 0.35 {mu}m CMOS technology and occupies an active area as small as 220 x 320 {mu}m{sup 2}, which is a reduction to 58% compared to state-of-the-art designs using technologies with the same feature size. Measurement results show that the LDO can deliver 0-60 mA output current with 54 {mu}A quiescent current consumption and the regulated output voltage is 1.8 V with an input voltage range from 2 to 3.3 V. (semiconductor integrated circuits)

  10. Full on-chip and area-efficient CMOS LDO with zero to maximum load stability using adaptive frequency compensation

    International Nuclear Information System (INIS)

    Ma Haifeng; Zhou Feng

    2010-01-01

    A full on-chip and area-efficient low-dropout linear regulator (LDO) is presented. By using the proposed adaptive frequency compensation (AFC) technique, full on-chip integration is achieved without compromising the LDO's stability in the full output current range. Meanwhile, the use of a compact pass transistor (the compact pass transistor serves as the gain fast roll-off output stage in the AFC technique) has enabled the LDO to be very area-efficient. The proposed LDO is implemented in standard 0.35 μm CMOS technology and occupies an active area as small as 220 x 320 μm 2 , which is a reduction to 58% compared to state-of-the-art designs using technologies with the same feature size. Measurement results show that the LDO can deliver 0-60 mA output current with 54 μA quiescent current consumption and the regulated output voltage is 1.8 V with an input voltage range from 2 to 3.3 V. (semiconductor integrated circuits)

  11. Working together to improve usability

    DEFF Research Database (Denmark)

    Nørgaard, Mie; Hornbæk, Kasper

    2010-01-01

    In theory, usability work is an important and well-integrated activity in developing software. In practice, collaboration on improving usability is ridden with challenges relating to conflicting professional goals, tight project schedules, and unclear usability findings. The authors study those...... challenges through 16 interviews with software developers, usability experts, and project managers. Four themes that are key challenges to successful interaction between stakeholders are identified: poor timing when delivering usability results, results lacking relevance, little respect for other disciplines...

  12. Experimental Determination of Operating and Maximum Power Transfer Efficiencies at Resonant Frequency in a Wireless Power Transfer System using PP Network Topology with Top Coupling

    Science.gov (United States)

    Ramachandran, Hema; Pillai, K. P. P.; Bindu, G. R.

    2017-08-01

    A two-port network model for a wireless power transfer system taking into account the distributed capacitances using PP network topology with top coupling is developed in this work. The operating and maximum power transfer efficiencies are determined analytically in terms of S-parameters. The system performance predicted by the model is verified with an experiment consisting of a high power home light load of 230 V, 100 W and is tested for two forced resonant frequencies namely, 600 kHz and 1.2 MHz. The experimental results are in close agreement with the proposed model.

  13. Usability Briefing for hospital design

    DEFF Research Database (Denmark)

    Fronczek-Munter, Aneta

    This PhD thesis is a contribution to an ongoing debate in Denmark about improving the building design processes of complex buildings, especially in relation to the current hospital developments. It provides knowledge about capturing user needs and defines the process model for usability briefing...... and evaluations, can be fed into briefing and design processes. This PhD thesis proposes methods for usability briefing.Usability is a concept similar to functionality, but usability depends on: subjective view of users, context, culture, situation and experience. Understanding usability is achieved by involving...... users. This PhD thesis extends the research in usability of buildings to include all building design phases, therefore not only proposes usability evaluations, but also defines usability briefing. Briefing, also called architectural programming, is usually understood as one of the first phases...

  14. Usability at the CELSTEC Medialab

    NARCIS (Netherlands)

    Storm, Jeroen; Kostons, Danny

    2009-01-01

    Storm, J., & Kostons, D. (2009). Usability at the CELSTEC MediaLab. Presentation about the usability testing, usability research and User Centered Design conducted at the CELSTEC MediaLab. July, 7, 2009, Heerlen, The Netherlands: Open University of the Netherlands.

  15. Software architecture analysis of usability

    NARCIS (Netherlands)

    Folmer, Eelke

    2005-01-01

    One of the qualities that has received increased attention in recent decades is usability. A software product with poor usability is likely to fail in a highly competitive market; therefore software developing organizations are paying more and more attention to ensuring the usability of their

  16. Usability of Discovery Portals

    OpenAIRE

    Bulens, J.D.; Vullings, L.A.E.; Houtkamp, J.M.; Vanmeulebrouk, B.

    2013-01-01

    As INSPIRE progresses to be implemented in the EU, many new discovery portals are built to facilitate finding spatial data. Currently the structure of the discovery portals is determined by the way spatial data experts like to work. However, we argue that the main target group for discovery portals are not spatial data experts but professionals with limited spatial knowledge, and a focus outside the spatial domain. An exploratory usability experiment was carried out in which three discovery p...

  17. Log files for testing usability

    NARCIS (Netherlands)

    Klein Teeselink, G.; Siepe, A.H.M.; Pijper, de J.R.

    1999-01-01

    The aim of this study is to gain insight in the usefulness of log file analysis as a method to evaluate the usability of individual interface components and their influence on the usability of the overall user interface. We selected a music player as application, with four different interfaces and

  18. Software architecture analysis of usability

    NARCIS (Netherlands)

    Folmer, E; van Gurp, J; Bosch, J; Bastide, R; Palanque, P; Roth, J

    2005-01-01

    Studies of software engineering projects show that a large number of usability related change requests are made after its deployment. Fixing usability problems during the later stages of development often proves to be costly, since many of the necessary changes require changes to the system that

  19. Assessment of the Usability of the Workbench Faraday Cage Method

    OpenAIRE

    Sørensen, Morten; Franek, Ondrej; Christensen, Søren K.; Pedersen, Gert Frølund; Ebert, Hans

    2011-01-01

    The workbench Faraday Cage method (WBFC) is a time efficient module pre-compliance test regarding radiated emission. This work investigates the method’s usability and credibility and concludes that for this particular case the WBFC perform a tolerable compliance test for frequencies below 360 MHz while it is essentially useless for higher frequencies.

  20. Integration of MSFC Usability Lab with Usability Testing

    Science.gov (United States)

    Cheng, Yiwei; Richardson, Sally

    2010-01-01

    As part of the Stage Analysis Branch, human factors engineering plays an important role in relating humans to the systems of hardware and structure designs of the new launch vehicle. While many branches are involved in the technical aspects of creating a launch vehicle, human factors connects humans to the scientific systems with the goal of improving operational performance and safety while reducing operational error and damage to the hardware. Human factors engineers use physical and computerized models to visualize possible areas for improvements to ensure human accessibility to components requiring maintenance and that the necessary maintenance activities can be accomplished with minimal risks to human and hardware. Many methods of testing are used to fulfill this goal, such as physical mockups, computerized visualization, and usability testing. In this analysis, a usability test is conducted to test how usable a website is to users who are and are not familiar with it. The testing is performed using participants and Morae software to record and analyze the results. This analysis will be a preliminary test of the usability lab in preparation for use in new spacecraft programs, NASA Enterprise, or other NASA websites. The usability lab project is divided into two parts: integration of the usability lab and a preliminary test of the usability lab.

  1. Long-term usability

    International Nuclear Information System (INIS)

    Holmgren, M.

    1998-01-01

    Longitudinal studies of the usability of a computer based system for process control has been performed. The whole life-cycle of one system has been of interest, as the problems are varying over time. Repeated measurements of the operators' experiences of this system have been made during 15 years. Of main interest have been the advantages/ disadvantages of computer based system for process control compared with conventional instrumentation. The results showed among other things that (1) computer based systems made it easier to control the process and increased security (2) age differences could be explained by other factors (3 ) expectations before the installation may influence the attitudes and use of equipment for quite some time In some questions the attitudes changed over time while in others they were quite stable, for example, in questions concerning preference for type of equipment. What do operators appreciate in a computer based system for process control? About 300 operators were asked about that. The main factor seems to include a reliable system with valid information that functions during disturbances. Hopefully new systems are designed with that in mind. (author)

  2. New usable technical specifications

    International Nuclear Information System (INIS)

    Webster, S.A.; Tomasi, L.T.; Bernier, R.A.

    1989-01-01

    After 2 yr of preparation, 1988 finally saw the nuclear industry writing operator-oriented technical specifications. This effort is a continuation of previous efforts to develop improved and usable standard technical specifications (STSs), and is being conducted by the four nuclear steam supply system vendor owners' groups under the auspices of the Nuclear Management Resources Council. Each participant is currently preparing a set of improved STSs based on a writer's guide that was developed through a combined industry effort. In May of 1987, a Human Factors Improvements to Technical Specifications (HFITS) task group was formed to prepare a writer's guide for improved, industrywide STSs. This task group was composed of two representatives from each owners' group, one with a human factors background and one with some operations background. Two documents were prepared in 6 months, a human factors report laying the groundwork for the considerations to go into technical specifications and a writer's guide for their preparation. This paper reports on the application of this writer's guide to the writing of improved STS

  3. Usability testing a practical guide for librarians

    CERN Document Server

    Blakiston, Rebecca

    2014-01-01

    Do you want to improve the usability of your library website, but feel that it is too difficult, time-consuming, or expensive? Usability Testing: A Practical Guide for Librarians will teach you how to make the case for usability testing, define your audience and their goals, select a usability testing method appropriate for your particular context, plan for an in-house usability test, conduct an effective in-house usability test, analyze usability test results, and create and implement a plan for ongoing, systematic usability testing. Step-by-step instructions, along with a myriad of examples,

  4. Problem Prioritization in Usability Evaluation:

    DEFF Research Database (Denmark)

    Hertzum, Morten

    2006-01-01

    Severity assessments enable prioritization of problems encountered during usability evaluations and thereby provide a device for guiding the utilization of design resources. However, designers' response to usability evaluations is also influenced by other factors, which may overshadow severity....... With the purpose of enhancing the impact of severity assessments, this study combines a field study of factors that influence the impact of evaluations with an experimental study of severity assessments made during usability inspections. The results show that even in a project receptive to input from evaluations...... their impact was highly dependent on conducting evaluations early. This accorded with an informal method that blended elements of usability evaluation and participatory design and could be extended with user-made severity assessments. The major cost associated with the evaluations was not finding but fixing...

  5. Neuroanatomical correlates of perceived usability

    DEFF Research Database (Denmark)

    Vi, Chi Thanh; Hornbæk, Kasper; Subramanian, Sriram

    2017-01-01

    Usability has a distinct subjective component, yet surprisingly little is known about its neural basis and relation to the neuroanatomy of aesthetics. To begin closing this gap, we conducted two functional magnetic resonance imaging studies in which participants were shown static webpages (in...... the first study) and videos of interaction with webpages (in the second study). The webpages were controlled so as to exhibit high and low levels of perceived usability and perceived aesthetics. Our results show unique links between perceived usability and brain areas involved in functions such as emotional...... processing (left fusiform gyrus, superior frontal gyrus), anticipation of physical interaction (precentral gyrus), task intention (anterior cingulate cortex), and linguistic processing (medial and bilateral superior frontal gyri). We use these findings to discuss the brain correlates of perceived usability...

  6. Usability in a cultural context

    DEFF Research Database (Denmark)

    Clemmensen, Torkil; Yammiyavar, Pradeep; Ørngreen, Rikke

    2010-01-01

    This paper focuses on presenting and discussing the aim, context, challenges, results, and impact of the Cultural usability project named as CultUsab. This project was a four year international research effort from 2006 to 2009, which was supported by a grant for the Danish Research Councils...... for Independent Research in Culture and Communication. The project aimed at innovating processes in Information and Communication Technology development through an understanding of culturally sensitive aspects of usability evaluation methods....

  7. Hello World! - Experiencing Usability Methods without Usability Expertise

    Science.gov (United States)

    Eriksson, Elina; Cajander, Åsa; Gulliksen, Jan

    How do you do usability work when no usability expertise is available? What happens in an organization when system developers, with no previous HCI knowledge, after a 3-day course, start applying usability methods, and particularly field studies? In order to answer these questions qualitative data were gathered through participatory observations, a feed back survey, field study documentation and interviews from 47 system developers from a public authority. Our results suggest that field studies enhance the developer’s understanding of the user perspective, and provide a more holistic overview of the use situation, but that some developers were unable to interpret their observations and see solutions to the users’ problems. The field study method was very much appreciated and has now become standard operating procedure within the organization. However, although field studies may be useful, it does not replace the need for usability pro fes sion als, as their knowledge is essential for more complex observations, analysis and for keeping the focus on usability.

  8. Responsibilities in the Usability Requirements Elicitation Process

    Directory of Open Access Journals (Sweden)

    Marianella Aveledo

    2008-12-01

    Full Text Available Like any other software system quality attribute, usability places requirements on software components. In particular, it has been demonstrated that certain usability features have a direct impact throughout the software process. This paper details an approach that looks at how to deal with certain usability features in the early software development stages. In particular, we consider usability features as functional usability requirements using patterns that have been termed usability patterns to elicit requirements. Additionally, we clearly establish the responsibilities of all the players at the usability requirements elicitation stage.

  9. An increased rectal maximum tolerable volume and long anal canal are associated with poor short-term response to biofeedback therapy for patients with anismus with decreased bowel frequency and normal colonic transit time.

    Science.gov (United States)

    Rhee, P L; Choi, M S; Kim, Y H; Son, H J; Kim, J J; Koh, K C; Paik, S W; Rhee, J C; Choi, K W

    2000-10-01

    Biofeedback is an effective therapy for a majority of patients with anismus. However, a significant proportion of patients still failed to respond to biofeedback, and little has been known about the factors that predict response to biofeedback. We evaluated the factors associated with poor response to biofeedback. Biofeedback therapy was offered to 45 patients with anismus with decreased bowel frequency (less than three times per week) and normal colonic transit time. Any differences in demographics, symptoms, and parameters of anorectal physiologic tests were sought between responders (in whom bowel frequency increased up to three times or more per week after biofeedback) and nonresponders (in whom bowel frequency remained less than three times per week). Thirty-one patients (68.9 percent) responded to biofeedback and 14 patients (31.1 percent) did not. Anal canal length was longer in nonresponders than in responders (4.53 +/- 0.5 vs. 4.08 +/- 0.56 cm; P = 0.02), and rectal maximum tolerable volume was larger in nonresponders than in responders. (361 +/- 87 vs. 302 +/- 69 ml; P = 0.02). Anal canal length and rectal maximum tolerable volume showed significant differences between responders and nonresponders on multivariate analysis (P = 0.027 and P = 0.034, respectively). This study showed that a long anal canal and increased rectal maximum tolerable volume are associated with poor short-term response to biofeedback for patients with anismus with decreased bowel frequency and normal colonic transit time.

  10. Assessment of the Usability of the Workbench Faraday Cage Method

    DEFF Research Database (Denmark)

    Sørensen, Morten; Franek, Ondrej; Christensen, Søren K.

    2011-01-01

    The workbench Faraday Cage method (WBFC) is a time efficient module pre-compliance test regarding radiated emission. This work investigates the method’s usability and credibility and concludes that for this particular case the WBFC perform a tolerable compliance test for frequencies below 360 MHz...

  11. Usability of PostgreSQL

    OpenAIRE

    Zeng, Xi

    2011-01-01

    My topic of the thesis is usability of PostgreSQL. It presents basic information aboutPostgreSQL, such as its history, function, and comparison with one of the most popular databases - MySQL. PostgreSQL has been tested in different environments and with different programming languages. The research is based on the documents from PostgreSQL official website.The thesis introduces and proves the usability and the compatibility of PostgreSQL. PostgreSQL has been installed on Windows workstation a...

  12. Cultural Cognition in Usability Evaluation

    DEFF Research Database (Denmark)

    Clemmensen, Torkil; Hertzum, Morten; Hornbæk, Kasper Anders Søren

    2009-01-01

    We discuss the impact of cultural differences on usability evaluations that are based on the thinking-aloud method (TA). The term ‘cultural differences' helps distinguish differences in the perception and thinking of Westerners (people from Western Europe and US citizens with European origins...... and evaluator. In conclusion, we point to the importance of matching the task presentation to users' cultural background, the different effects of thinking aloud on task performance between Easterners and Westerners, the differences in nonverbal behaviour that affect usability problem detection, and, finally...

  13. Cultural Cognition in Usability Evaluation

    DEFF Research Database (Denmark)

    Clemmensen, Torkil; Hertzum, Morten; Hornbæk, Kasper Anders Søren

    2009-01-01

    We discuss the impact of cultural differences on usability evaluations that are based on the thinking-aloud method (TA). The term ‘cultural differences’ helps distinguish differences in the perception and thinking of Westerners (people from Western Europe and US citizens with European origins...... and evaluator. In conclusion, we point to the importance of matching the task presentation to users’ cultural background, the different effects of thinking aloud on task performance between Easterners and Westerners, the differences in nonverbal behaviour that affect usability problem detection, and, finally...

  14. Defining Usability of PN Services

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh; Ahola, Titta; Fleury, Alexandre

    In this deliverable usability and user experience are defined in relation to MAGNET Beyond technologies, and it is described how the main MAGNET Beyond concepts can be evaluated through the involvement of users. The concepts include the new "Activity based communication approach" for interacting...... with the MAGNET Beyond system, as well as the core concepts: Personal Network, Personal Network-Federation, Service Discovery, User Profile Management, Personal Network Management, Privacy and Security and Context Awareness. The overall plans for the final usability evaluation are documented based on the present...

  15. New approach of determinations of earthquake moment magnitude using near earthquake source duration and maximum displacement amplitude of high frequency energy radiation

    Energy Technology Data Exchange (ETDEWEB)

    Gunawan, H.; Puspito, N. T.; Ibrahim, G.; Harjadi, P. J. P. [ITB, Faculty of Earth Sciences and Tecnology (Indonesia); BMKG (Indonesia)

    2012-06-20

    The new approach method to determine the magnitude by using amplitude displacement relationship (A), epicenter distance ({Delta}) and duration of high frequency radiation (t) has been investigated for Tasikmalaya earthquake, on September 2, 2009, and their aftershock. Moment magnitude scale commonly used seismic surface waves with the teleseismic range of the period is greater than 200 seconds or a moment magnitude of the P wave using teleseismic seismogram data and the range of 10-60 seconds. In this research techniques have been developed a new approach to determine the displacement amplitude and duration of high frequency radiation using near earthquake. Determination of the duration of high frequency using half of period of P waves on the seismograms displacement. This is due tothe very complex rupture process in the near earthquake. Seismic data of the P wave mixing with other wave (S wave) before the duration runs out, so it is difficult to separate or determined the final of P-wave. Application of the 68 earthquakes recorded by station of CISI, Garut West Java, the following relationship is obtained: Mw = 0.78 log (A) + 0.83 log {Delta}+ 0.69 log (t) + 6.46 with: A (m), d (km) and t (second). Moment magnitude of this new approach is quite reliable, time processing faster so useful for early warning.

  16. New approach of determinations of earthquake moment magnitude using near earthquake source duration and maximum displacement amplitude of high frequency energy radiation

    Science.gov (United States)

    Gunawan, H.; Puspito, N. T.; Ibrahim, G.; Harjadi, P. J. P.

    2012-06-01

    The new approach method to determine the magnitude by using amplitude displacement relationship (A), epicenter distance (Δ) and duration of high frequency radiation (t) has been investigated for Tasikmalaya earthquake, on September 2, 2009, and their aftershock. Moment magnitude scale commonly used seismic surface waves with the teleseismic range of the period is greater than 200 seconds or a moment magnitude of the P wave using teleseismic seismogram data and the range of 10-60 seconds. In this research techniques have been developed a new approach to determine the displacement amplitude and duration of high frequency radiation using near earthquake. Determination of the duration of high frequency using half of period of P waves on the seismograms displacement. This is due tothe very complex rupture process in the near earthquake. Seismic data of the P wave mixing with other wave (S wave) before the duration runs out, so it is difficult to separate or determined the final of P-wave. Application of the 68 earthquakes recorded by station of CISI, Garut West Java, the following relationship is obtained: Mw = 0.78 log (A) + 0.83 log Δ + 0.69 log (t) + 6.46 with: A (m), d (km) and t (second). Moment magnitude of this new approach is quite reliable, time processing faster so useful for early warning.

  17. New approach of determinations of earthquake moment magnitude using near earthquake source duration and maximum displacement amplitude of high frequency energy radiation

    International Nuclear Information System (INIS)

    Gunawan, H.; Puspito, N. T.; Ibrahim, G.; Harjadi, P. J. P.

    2012-01-01

    The new approach method to determine the magnitude by using amplitude displacement relationship (A), epicenter distance (Δ) and duration of high frequency radiation (t) has been investigated for Tasikmalaya earthquake, on September 2, 2009, and their aftershock. Moment magnitude scale commonly used seismic surface waves with the teleseismic range of the period is greater than 200 seconds or a moment magnitude of the P wave using teleseismic seismogram data and the range of 10-60 seconds. In this research techniques have been developed a new approach to determine the displacement amplitude and duration of high frequency radiation using near earthquake. Determination of the duration of high frequency using half of period of P waves on the seismograms displacement. This is due tothe very complex rupture process in the near earthquake. Seismic data of the P wave mixing with other wave (S wave) before the duration runs out, so it is difficult to separate or determined the final of P-wave. Application of the 68 earthquakes recorded by station of CISI, Garut West Java, the following relationship is obtained: Mw = 0.78 log (A) + 0.83 log Δ+ 0.69 log (t) + 6.46 with: A (m), d (km) and t (second). Moment magnitude of this new approach is quite reliable, time processing faster so useful for early warning.

  18. Usability Testing: A Case Study.

    Science.gov (United States)

    Chisman, Janet; Walbridge, Sharon; Diller, Karen

    1999-01-01

    Discusses the development and results of usability testing of Washington State University's Web-based OPAC (online public access catalog); examines how easily users could navigate the catalog and whether they understood what they were seeing; and identifies problems and what action if any was taken. (LRW)

  19. Improving Usability of Passphrase Authentication

    DEFF Research Database (Denmark)

    Nielsen, Glen; Vedel, Michael; Jensen, Christian D.

    2014-01-01

    . This is done to ensure an appropriate degree of security, but instead, it makes it difficult for users to remember their password, which results in passwords that are either insecure, but easy to remember, or written down on paper. In this paper we address the problem of usability in user authentication...

  20. Usability Problems in a Home Telemedicine System

    DEFF Research Database (Denmark)

    Bruun, Anders; Stage, Jan

    2010-01-01

    a high level of usability in order to enable their users to employ the required functionality, especially if the target user group is elderly people. This paper reports from a usability evaluation of a home telemedicine system. Five elderly persons carried out specified tasks with the system, and based...... on that we identified usability problems with the system. The problems are presented, analysed in relation to 12 different usability themes and related to results from other evaluations of similar systems....

  1. Usability Testing Of Web Mapping Portals

    Directory of Open Access Journals (Sweden)

    Petr Voldán

    2011-05-01

    Full Text Available This study presents a usability testing as method, which can be used to improve controlling of web map sites. Study refers to the basic principles of this method and describes particular usability tests of mapping sites. In this paper are identified potential usability problems of web sites: Amapy.cz, Google maps and Mapy.cz. The usability testing was focused on problems related with user interfaces, addresses searching and route planning of the map sites.

  2. Course management systems from a usability perspective

    CSIR Research Space (South Africa)

    Padayachee, I

    2011-01-01

    Full Text Available (with knowledge of usability engineering and system domain knowledge) who inspect the Indira Padayachee, Paula Kotz? and Alta van der Merwe 302 interface and determine its compliance with recognized usability principles (the ?heuristics... presents a summary of the results of the severity rating. Table 2: Severity Rating Scale for Usability Problems (Nielsen 2007b) 0 I don?t agree that this is a usability problem at all 1 Cosmetic problem only: need not be fixed unless there is extra...

  3. Towards Evidence Based Usability in Health Informatics?

    NARCIS (Netherlands)

    Marcilly, Romaric; Peute, Linda W.; Beuscart-Zephir, Marie-Catherine; Jaspers, Monique W.

    2015-01-01

    In a Health Information Technology (HIT) regulatory context in which the usability of this technology is more and more a critical issue, there is an increasing need for evidence based usability practice. However, a clear definition of evidence based usability practice and how to achieve it is still

  4. The Evaluator Effect in Usability Tests

    DEFF Research Database (Denmark)

    Jacobsen, Niels Ebbe; Hertzum, Morten; John, Bonnie E.

    1998-01-01

    Usability tests are applied in industry to evaluate systems and in research as a yardstick for other usability evaluation methods. However, one potential threat to the reliability of usability tests has been left unaddressed: the evaluator effect. In this study, four evaluators analyzed four vide...

  5. Understanding Usability Work as a Human Activity

    DEFF Research Database (Denmark)

    Nørgaard, Mie

    Three core themes are explored in eight papers: Usability work as a human activity, usability practice and methods, and persuasiveness of evaluation results and feedback. We explore how usability work is much more than methods and work procedures, and argue that maturing our understanding...

  6. Signature of a possible relationship between the maximum CME speed index and the critical frequencies of the F1 and F2 ionospheric layers: Data analysis for a mid-latitude ionospheric station during the solar cycles 23 and 24

    Science.gov (United States)

    Kilcik, Ali; Ozguc, Atila; Yiǧit, Erdal; Yurchyshyn, Vasyl; Donmez, Burcin

    2018-06-01

    We analyze temporal variations of two solar indices, the monthly mean Maximum CME Speed Index (MCMESI) and the International Sunspot Number (ISSN) as well as the monthly median ionospheric critical frequencies (foF1, and foF2) for the time period of 1996-2013, which covers the entire solar cycle 23 and the ascending branch of the cycle 24. We found that the maximum of foF1 and foF2 occurred respectively during the first and second maximum of the ISSN solar activity index in the solar cycle 23. We compared these data sets by using the cross-correlation and hysteresis analysis and found that both foF1 and foF2 show higher correlation with ISSN than the MCMESI during the investigated time period, but when significance levels are considered correlation coefficients between the same indices become comparable. Cross-correlation analysis showed that the agreement between these data sets (solar indices and ionospheric critical frequencies) is better pronounced during the ascending phases of solar cycles, while they display significant deviations during the descending phase. We conclude that there exists a signature of a possible relationship between MCMESI and foF1 and foF2, which means that MCMESI could be used as a possible indicator of solar and geomagnetic activity, even though other investigations are needed.

  7. The impact of usability reports and user test observations on developers understanding of usability data

    DEFF Research Database (Denmark)

    Høegh, Rune Thaarup; Nielsen, Christian Monrad; Pedersen, Michael Bach

    2006-01-01

    of the system. This article presents results from an exploratory study of 2 ways of providing feedback from a usability evaluation: observation of user tests and reading usability reports. A case study and a field experiment were used to explore how observation and usability reports impact developers......' understanding of usability data. The results indicate that observation of user tests facilitated a rich understanding of usability problems and created empathy with the users and their work. The usability report had a strong impact on the developers' understanding of specific usability problems and supported...

  8. Library Website Usability Test Project

    KAUST Repository

    Ramli, Rindra M.; Bukhari, Duaa

    2013-01-01

    This usability testing project was conducted to elicit an understanding of our community use of the library website. The researchers wanted to know how our users are interacting with the library website and the ease of obtaining relevant information from the website. The methodology deployed was computer user testing where participants are made to answer several questions and executing the actions on the library website. Their actions are recorded via Techsmith Camtasia software for later analysis by the researchers.

  9. Library Website Usability Test Project

    KAUST Repository

    Ramli, Rindra M.

    2013-06-01

    This usability testing project was conducted to elicit an understanding of our community use of the library website. The researchers wanted to know how our users are interacting with the library website and the ease of obtaining relevant information from the website. The methodology deployed was computer user testing where participants are made to answer several questions and executing the actions on the library website. Their actions are recorded via Techsmith Camtasia software for later analysis by the researchers.

  10. Increasing the impact of usability work in software development

    DEFF Research Database (Denmark)

    Uldall-Espersen, Tobias; Frøkjær, Erik

    2006-01-01

    Usability, Case Study, Software Engineering, Software Quality, Organizational Impact, Usability Requirement Management, CHI 2007 workshop......Usability, Case Study, Software Engineering, Software Quality, Organizational Impact, Usability Requirement Management, CHI 2007 workshop...

  11. Commentary: Usability – A Sensitizing Concept

    DEFF Research Database (Denmark)

    Hertzum, Morten

    2018-01-01

    In his article “The Usability Construct: A Dead End?”, Tractinsky (in Human-Computer Interaction) contends that for scientific research on usability to progress, the usability construct should be unbundled and replaced by well-defined constructs. This contention is presented as the conclusion...... that follows naturally from taking a scientist’s viewpoint on usability. Similar calls for definitive concepts – constructs in Tractinsky’s terminology – have been made in other scientific fields with concepts as ambiguous as that of usability. But counterarguments have also been presented....

  12. Software Development and Feedback from Usability Evaluations

    DEFF Research Database (Denmark)

    Høegh, Rune Thaarup

    2008-01-01

    This paper presents a study of the strengths and weaknesses of written, multimedia and oral feedback from usability evaluations to developers. The strengths and weaknesses are related to how well the feedback supports the developers in addressing usability problems in a software system. The study...... concludes that using the traditional written usability report, as the only form of feedback from usability evaluations is associated with problems related to the report not supporting the process of addressing the usability problems. The report is criticized for representing an overwhelming amount...... of information, while still not offering the required information to address usability problems. Other forms of feedback, such as oral or multimedia feedback helps the developer in understanding the usability problems better, but are on the other hand less cost-effective than a written description....

  13. Developer Driven and User Driven Usability Evaluations

    DEFF Research Database (Denmark)

    Bruun, Anders

    2013-01-01

    Usability evaluation provide software development teams with insights on the degree to which a software application enables a user to achieve his/her goals, how fast these goals can be achieved, how easy it is to learn and how satisfactory it is in use Although usability evaluations are crucial...... in the process of developing software systems with a high level of usability, its use is still limited in the context of small software development companies. Several approaches have been proposed to support software development practitioners (SWPs) in conducting usability evaluations, and my thesis explores two...... of these: 1) The first approach is to support SWPs by training them to drive usability evaluations. 2) The second approach to support SWPs involves minimalist training of end users to drive usability evaluations. In related work, a set of five quality criteria for usability evaluations is applied...

  14. Usability and Interaction Design in West Africa

    DEFF Research Database (Denmark)

    Sørensen, Jannick Kirk

    Good usability is important in all ICT solutions. To achieve good usability, a good praxis for interaction design is needed. Usability and interaction design have however emerged and established itself in a North European and US context. The ICT industry in Africa do not have the same resources...... for user-involvement and participatory design be directly transferred? How can interaction design and usability be cared for in African ICT development context, given the resources available? This paper aims to initiate a discussion of the conditions for interaction design and usability in West Africa...... in the field of interaction design as in the developed world. While good usability and good user experiences are important to all users of ICT, the question is whether the methods and techniques that were mainly developed in Scandinavia, Europe and US are suitable for ICT development in Africa? Can ideals...

  15. Advancing Usability Evaluation through Human Reliability Analysis

    International Nuclear Information System (INIS)

    Ronald L. Boring; David I. Gertman

    2005-01-01

    This paper introduces a novel augmentation to the current heuristic usability evaluation methodology. The SPAR-H human reliability analysis method was developed for categorizing human performance in nuclear power plants. Despite the specialized use of SPAR-H for safety critical scenarios, the method also holds promise for use in commercial off-the-shelf software usability evaluations. The SPAR-H method shares task analysis underpinnings with human-computer interaction, and it can be easily adapted to incorporate usability heuristics as performance shaping factors. By assigning probabilistic modifiers to heuristics, it is possible to arrive at the usability error probability (UEP). This UEP is not a literal probability of error but nonetheless provides a quantitative basis to heuristic evaluation. When combined with a consequence matrix for usability errors, this method affords ready prioritization of usability issues

  16. Work-domain knowledge in usability evaluation

    DEFF Research Database (Denmark)

    Følstad, Asbjørn; Hornbæk, Kasper

    2010-01-01

    Usability evaluation helps to determine whether interactive systems support users in their work tasks. However, knowledge about those tasks and, more generally, about the work-domain is difficult to bring to bear on the processes and outcome of usability evaluation. One way to include such work......-domain knowledge might be Cooperative Usability Testing, an evaluation method that consists of (a) interaction phases, similar to classic usability testing, and (b) interpretation phases, where the test participant and the moderator discuss incidents and experiences from the interaction phases. We have studied...... whether such interpretation phases improve the relevance of usability evaluations in the development of work-domain specific systems. The study included two development cases. We conclude that the interpretation phases generate additional insight and redesign suggestions related to observed usability...

  17. Distributed user interfaces usability and collaboration

    CERN Document Server

    Lozano, María D; Tesoriero, Ricardo; Penichet, Victor MR

    2013-01-01

    Written by international researchers in the field of Distributed User Interfaces (DUIs), this book brings together important contributions regarding collaboration and usability in Distributed User Interface settings. Throughout the thirteen chapters authors address key questions concerning how collaboration can be improved by using DUIs, including: in which situations a DUI is suitable to ease the collaboration among users; how usability standards can be used to evaluate the usability of systems based on DUIs; and accurately describe case studies and prototypes implementing these concerns

  18. Usable security history, themes, and challenges

    CERN Document Server

    Garfinkel, Simson

    2014-01-01

    There has been roughly 15 years of research into approaches for aligning research in Human Computer Interaction with computer Security, more colloquially known as ``usable security.'' Although usability and security were once thought to be inherently antagonistic, today there is wide consensus that systems that are not usable will inevitably suffer security failures when they are deployed into the real world. Only by simultaneously addressing both usability and security concerns will we be able to build systems that are truly secure. This book presents the historical context of the work to dat

  19. Usability evaluation of the interactive Personal Patient Profile-Prostate decision support system with African American men.

    Science.gov (United States)

    Jaja, Cheedy; Pares-Avila, Jose; Wolpin, Seth; Berry, Donna

    2010-04-01

    The Personal Patient Profile-Prostate (P4) program is an interactive Web-based decision support system that provides men with localized prostate cancer customized education and coaching with which to make the best personal treatment decision. This study assessed functionality and usability of the P4 program and identified problems in user-computer interaction in a sample of African American men. Usability testing was conducted with 12 community-dwelling African American adult men. The health status of participants was not known or collected by the research team. Each participant worked with the P4 program and provided simultaneous feedback using the "think aloud" technique. Handwritten field notes were collated and assigned to 3 standard coded categories. Aspects of P4 program usability was made based on common issues in the assigned categories. Summary statistics were derived for types and frequency of usability issues noted in the coded data. Twelve participants reported a total of 122 usability comments, with a mean of 9 usability comments. The most common usability issue by participant was completeness of information content, which comprised 53 (43%) of the total issues. Comprehensibility of text and graphics was second, comprising 51 (42%) of the total issues. This study provided initial inventory of usability issues for community African American men that may potentially interfere with application of the P4 system in the community setting and overall system usability, confirming the need for usability testing of a culturally appropriate Internet-based decision support system before community application.

  20. Comparative usability of modern anaesthesia ventilators: a human factors study.

    Science.gov (United States)

    Spaeth, J; Schweizer, T; Schmutz, A; Buerkle, H; Schumann, S

    2017-11-01

    The anaesthesia ventilator represents the key equipment for intraoperative respiratory care. Improper operation of this device may threaten a patient's health. A self-explanatory interface facilitates handling and decreases the risk of operating errors. This study systematically evaluates the usability of user interfaces in four modern anaesthesia ventilators. Twenty naïve operators were asked to execute 20 tasks on each of four different anaesthesia ventilators (Avance CS2™, GE Healthcare; Flow-i™, Maquet; and Perseus™ and Primus™, Dräger) in a randomized order. The success of task execution, frequency of requests for assistance, and processing times were recorded. During the tasks, the operators' visual focus was measured via eye-tracking. Additionally, subjective assessments of usability were evaluated by a standardized questionnaire. For comparison, six experienced operators undertook the same protocol. The overall rate of falsely executed tasks was low. Naïve operators requested assistance least when using the Perseus (26). Pooled processing times were shortest for the Perseus (222 s), followed by the Primus (223 s), the Avance (238 s), and the Flow-i (353 s). Task-specific processing times differed considerably between the devices. Eye-tracking analyses revealed associated interface issues that impeded the operators' performance. Operators rated usability best for the Perseus [mean (sd): 67 (17) arbitrary units] and worst for the Flow-i [50 (16) arbitrary units]. Results from experienced operators support these findings by trend. The usability of modern anaesthesia ventilators differs considerably. Interface issues of specific tasks impair the operator's efficiency. Eliminating the specific usability issues might improve the operator's performance and, as a consequence, the patient's safety. © The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please

  1. Usability Prediction & Ranking of SDLC Models Using Fuzzy Hierarchical Usability Model

    Science.gov (United States)

    Gupta, Deepak; Ahlawat, Anil K.; Sagar, Kalpna

    2017-06-01

    Evaluation of software quality is an important aspect for controlling and managing the software. By such evaluation, improvements in software process can be made. The software quality is significantly dependent on software usability. Many researchers have proposed numbers of usability models. Each model considers a set of usability factors but do not cover all the usability aspects. Practical implementation of these models is still missing, as there is a lack of precise definition of usability. Also, it is very difficult to integrate these models into current software engineering practices. In order to overcome these challenges, this paper aims to define the term `usability' using the proposed hierarchical usability model with its detailed taxonomy. The taxonomy considers generic evaluation criteria for identifying the quality components, which brings together factors, attributes and characteristics defined in various HCI and software models. For the first time, the usability model is also implemented to predict more accurate usability values. The proposed system is named as fuzzy hierarchical usability model that can be easily integrated into the current software engineering practices. In order to validate the work, a dataset of six software development life cycle models is created and employed. These models are ranked according to their predicted usability values. This research also focuses on the detailed comparison of proposed model with the existing usability models.

  2. Usable Interface Design for Everyone

    Science.gov (United States)

    de Castro Lozano, Carlos; Salcines, Enrique García; Sainz de Abajo, Beatriz; Burón Fernández, F. Javier; Ramírez, José Miguel; Recellado, José Gabriel Zato; Montoya, Rafael Sanchez; Bell, John; Marin, Francisco Alcantud

    When designing "interfaces for everyone" for interactive systems, it is important to consider factors such as cost, the intended market, the state of the environment, etc. User interfaces are fundamental for the developmental process in any application, and its design must be contemplated from the start. Of the distinct parts of a system (hardware and software), it is the interface that permits the user access to computer resources. The seven principles of "Universal Design" or "Design for Everyone" focus on a universal usable design, but at the same time acknowledge the influences of internal and external factors. Structural changes in social and health services could provide an increase in the well-being of a country's citizens through the use of self-care programming and proactive management/prevention of disease. Automated home platforms can act as an accessibility instrument which permits users to avoid, compensate, mitigate, or neutralize the deficiencies and dependencies caused by living alone.

  3. Usability Study of a Computer-Based Self-Management System for Older Adults with Chronic Diseases

    Science.gov (United States)

    Tao, Da

    2012-01-01

    Background Usability can influence patients’ acceptance and adoption of a health information technology. However, little research has been conducted to study the usability of a self-management health care system, especially one geared toward elderly patients. Objective This usability study evaluated a new computer-based self-management system interface for older adults with chronic diseases, using a paper prototype approach. Methods Fifty older adults with different chronic diseases participated. Two usability evaluation methods were involved: (1) a heuristics evaluation and (2) end-user testing with a think-aloud testing method, audio recording, videotaping, and interviewing. A set of usability metrics was employed to determine the overall system usability, including task incompletion rate, task completion time, frequency of error, frequency of help, satisfaction, perceived usefulness, and perceived ease of use. Interviews were used to elicit participants’ comments on the system design. The quantitative data were analyzed using descriptive statistics and the qualitative data were analyzed for content. Results The participants were able to perform the predesigned self-management tasks with the current system design and they expressed mostly positive responses about the perceived usability measures regarding the system interface. However, the heuristics evaluation, performance measures, and interviews revealed a number of usability problems related to system navigation, information search and interpretation, information presentation, and readability. Design recommendations for further system interface modifications were discussed. Conclusions This study verified the usability of the self-management system developed for older adults with chronic diseases. Also, we demonstrated that our usability evaluation approach could be used to quickly and effectively identify usability problems in a health care information system at an early stage of the system development

  4. Evaluation of Usability Utilizing Markov Models

    Science.gov (United States)

    Penedo, Janaina Rodrigues; Diniz, Morganna; Ferreira, Simone Bacellar Leal; Silveira, Denis S.; Capra, Eliane

    2012-01-01

    Purpose: The purpose of this paper is to analyze the usability of a remote learning system in its initial development phase, using a quantitative usability evaluation method through Markov models. Design/methodology/approach: The paper opted for an exploratory study. The data of interest of the research correspond to the possible accesses of users…

  5. Merits of usability testing for PACS selection

    NARCIS (Netherlands)

    Jorritsma, Wiard; Cnossen, Fokie; van Ooijen, Peter M. A.

    Objectives: To compare the usability of different Picture Archiving and Communication System (PACS) workstations, determine whether a usability test has added value with respect to the traditional way of comparing PACSs based on functional requirements, and to evaluate the appropriateness of a

  6. Usability evaluations in user-centred design

    NARCIS (Netherlands)

    Ruyter, de B.E.R.; Vet, de J.H.M.

    1997-01-01

    Improving usability of consumer applications has been the focus of much research. Estimating the advantage of these efforts, however, still is very cumbersome since evaluating product improvements in terms of their usability requires good measuring methods and tools. In this paper activities in the

  7. Exploring the value of usability feedback formats

    DEFF Research Database (Denmark)

    Nørgaard, Mie; Hornbæk, Kasper Anders Søren

    2009-01-01

    The format used to present feedback from usability evaluations to developers affects whether problems are understood, accepted, and fixed. Yet, little research has investigated which formats are the most effective. We describe an explorative study where three developers assess 40 usability findings...... presented using five feedback formats. Our usability findings comprise 35 problems and 5 positive comments. Data suggest that feedback serves multiple purposes. Initially, feedback must convince developers about the relevance of a problem and convey an understanding of this. Feedback must next be easy...... working with the feedback to address the usability problems, there were no significant differences among the developers' ratings of the value of the different formats. This suggests that all of the formats may serve equally well as reminders in later stages of working with usability problems...

  8. Qualitative Marketing Research Through Usability Testing

    Directory of Open Access Journals (Sweden)

    Orzan Mihai

    2008-04-01

    Full Text Available Usability is an attribute of any good product, just as its functionality. It refers mainly to the utility of a product for its indented users, as well as to its ease of use. And whilst a correct functionality is critical for the commercial success of any product, its value comes through the human needs that it fulfills, which is determined through various marketing research techniques. In parallel, the IT&C community has developed in the last two decades its own type of research, called usability testing, used mainly to evaluate interface ease of use and all usability problems associated with.software products. This article aims at finding the right place for usability testing and usability professionals in the marketing community, as well as drawing a wider picture, from a marketing research perspective, on one of the most popular topics in IT&C community for the benefit of marketing scholars and professionals.

  9. Tracing Impact in a Usability Improvement Process

    DEFF Research Database (Denmark)

    Uldall-Espersen, Tobias; Frøkjær, Erik; Hornbæk, Kasper Anders Søren

    2008-01-01

    Analyzing usability improvement processes as they take place in real-life organizations is necessary to understand the practice of usability work. This paper describes a case study where the usability of an information system is improved and a relationship between the improvements...... and the evaluation efforts is established. Results show that evaluation techniques complemented each other by suggesting different kinds of usability improvement. Among the techniques applied, a combination of questionnaires and Metaphors of Human Thinking (MOT) showed the largest mean impact and MOT produced...... the largest number of impacts. Logging of real-life use of the system over 6 months indicated six aspects of improved usability, where significant differences among evaluation techniques were found. Concerning five of the six aspects Think Aloud evaluations and the above-mentioned combination of questionnaire...

  10. Usability Evaluation in a Digitally Emerging Country

    DEFF Research Database (Denmark)

    Lizano, Fulvio; Sandoval, Maria Marta; Bruun, Anders

    2013-01-01

    Several emerging countries experience increasing software development activities. With the purpose of provide useful feedback on possible courses of action for increasing application of usability evaluation in such countries, this paper explores the status of usability evaluation in a digitally...... emerging country. Our aim is to identifying common characteristics or behavioral patterns that could be compared with digitally advanced countries. We used an online survey answered by 26 software development organizations, which gave a snapshot of the application of usability evaluation...... in these organizations. We found many similarities with advanced countries, several completely new obstacles more connected with software development matters and a relatively positive improvement in the lack of “usability culture”. These findings suggest good conditions to improve conduction of usability evaluations...

  11. Usability of Public Administration Electronic Forms

    Directory of Open Access Journals (Sweden)

    Miloslav Hub

    2015-06-01

    Full Text Available This paper is focused on the testing and evaluating of public administration electronic forms from the usability point of view. Its objective is to design a suitable methodology for usability testing of electronic forms and their description and distribution to public administration information systems professionals. Firstly, methods of usability engineering are summarized and a suitable method for usability testing and evaluation of electronic forms is selected. Farther, the methodology of electronic forms usability testing that uses the selected method is suggested. In the last part of the paper the case study that uses the proposed methodology is suggested and performed. The main benefit of the work is the design of testing methodology and proposition of the set of recommendations for new public administration electronic forms design.

  12. From Playability to a Hierarchical Game Usability Model

    OpenAIRE

    Nacke, Lennart E.

    2010-01-01

    This paper presents a brief review of current game usability models. This leads to the conception of a high-level game development-centered usability model that integrates current usability approaches in game industry and game research.

  13. Improving Public Relations Web Sites through Usability Research.

    Science.gov (United States)

    Hallahan, Kirk

    2001-01-01

    Argues that usability research has particular relevance for enhancing the effectiveness of websites. Examines the nature and value of usability research, and the elements of an effective website based on usability principles. (SR)

  14. Usability and Accessibility of Air Force Intranet Web Sites

    National Research Council Canada - National Science Library

    Bentley, Richard S

    2006-01-01

    .... The Technology Acceptance Model suggests that information systems must not only be useful but also be usable and a large body of usability engineering knowledge exists to support usable design. In addition, the U.S...

  15. An Intelligent Framework for Website Usability

    Directory of Open Access Journals (Sweden)

    Alexiei Dingli

    2014-01-01

    Full Text Available With the major advances of the Internet throughout the past couple of years, websites have come to play a central role in the modern marketing business program. However, simply owning a website is not enough for a business to prosper on the Web. Indeed, it is the level of usability of a website that determines if a user stays or abandons it for another competing one. It is therefore crucial to understand the importance of usability on the web, and consequently the need for its evaluation. Nonetheless, there exist a number of obstacles preventing software organizations from successfully applying sound website usability evaluation strategies in practice. From this point of view automation of the latter is extremely beneficial, which not only assists designers in creating more usable websites, but also enhances the Internet users’ experience on the Web and increases their level of satisfaction. As a means of addressing this problem, an Intelligent Usability Evaluation (IUE tool is proposed that automates the usability evaluation process by employing a Heuristic Evaluation technique in an intelligent manner through the adoption of several research-based AI methods. Experimental results show there exists a high correlation between the tool and human annotators when identifying the considered usability violations.

  16. Evaluation of Virtual Teaching-Learning Environments based on usability standards

    Directory of Open Access Journals (Sweden)

    Jose I. Cocunubo-Suarez

    2018-01-01

    Full Text Available The main objective of this review article is to determine the necessary sub-characteristics or aspects for the evaluation of Virtual Teaching-Learning Environments (VTLEs as final or finished products based on ISO 9126, 14598 and 25000-SQuaRE standards. A systematic information search was carried out. A total of 108 documents were retrieved about subjects such as web usability, virtual learning environments, usability, educational software, educational web evaluation, usability evaluation and web usability evaluation. Out of the 108 documents, 70 were selected by inclusion and exclusion analysis. The eight subfeatures of greater statistical frequency were identified among the subset of documents and then integrated as a proposal for standard 25000-SQuaRE.

  17. The Software Therapist: Usability Problem Diagnosis Through Latent Semantic Analysis

    National Research Council Canada - National Science Library

    Sparks, Randall; Hartson, Rex

    2006-01-01

    The work we report on here addresses the problem of low return on investment in software usability engineering and offers support for usability practitioners in identifying, understanding, documenting...

  18. Three Contexts for Evaluating Organizational Usability

    DEFF Research Database (Denmark)

    Hertzum, Morten

    2018-01-01

    Organizational usability is about the match between the user and the system, between the organization and the system, and between the environment and the system. While the first of these matches can, to a large extent, be evaluated in the lab, the two others cannot. Organizational usability must......, provide a brief example, and discuss the challenges it presents. To strengthen the focus on evaluation in the three contexts we propose the measurement of specified effects, combined with a sensitivity toward emergent effects. Incorporating effects in the evaluation of organizational usability makes...

  19. The effects of protoype medium on usability testing.

    Science.gov (United States)

    Boothe, Chase; Strawderman, Lesley; Hosea, Ethan

    2013-11-01

    Inconsistencies among testing methods and results in previous research prompted this study that builds upon a systematic usability testing research framework to better understand how interface medium influences users' abilities to detect usability flaws in applications. Interface medium was tested to identify its effects on users' perceptions of usability and abilities to detect usability problems and severe usability problems. Results indicated that medium has no effect on users' abilities to detect usability problems or perceptions of usability. However, results did indicate an interaction between the medium and the tested application in which users were able to identify significantly more usability problems on a higher fidelity medium using a particular application. Results also indicated that as users' perceptions of an application's usability increases, the users are less able to detect usability problems in that application. Usability testing should begin early in the design process, even if low fidelity mediums will be used. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  20. Usability Evaluation of www.budget.com

    DEFF Research Database (Denmark)

    Bruun, Anders; Jensen, Janne Jul; Skov, Mikael B.

    This report presents the results of a usability evaluation of the budget.com website. The evaluation was carried out by a team of 4 HCI experts, and it involved 10 potential users. The evaluation is based on measurement of (1) task completion time, (2) task completion, (3) user satisfaction and (4......) perceived workload. We have also analyzed the user interaction with the website for (5) usability problems. Through the evaluation, we have found the following weaknesses of the website:   Reservation takes considerably more time than promised. The website indicates that a reservation can be made in 60...... is not useful for specific purposes. The user satisfaction is generally low. Except one high and two low scores, the user satisfaction was in the middle range. There are too many severe usability problems. The evaluation identified a considerable number of usability problems. 5 of them were critical which means...

  1. Apathy towards the Integration of Usability Work

    DEFF Research Database (Denmark)

    Wale-Kolade, Adeola; Nielsen, Peter Axel

    2016-01-01

    In this article we report from a case study of a software development organization and we study in particular the developers’ and product managers’ attitudes towards integrating usability work into software development. We offer explanations based on system justification theory illuminating what...... would-be integrators might be up against. The analysis shows how the developers only pay lip service to usability work and how they treat users superficially. It further shows how that leads to stereotyping of usability designers and users in order to preserve status quo, and how internalization...... of inequality between the developers and usability designers rationalizes the preservation of status quo. These findings will have significant implications for managers of software development....

  2. A usability test is not an interview

    DEFF Research Database (Denmark)

    Hertzum, Morten

    2016-01-01

    Usability tests are conducted to gauge users’ experience with a system, preferably before it is released for real use, and thereby find any problems that prevent users from completing their tasks, slow them down, or otherwise degrade their user experience. Such tests are important to successful...... systems development, yet test procedures vary and the quality of test results is sometimes contested. While there is no single accepted procedure for usability specialists to follow when conducting usability tests, these tests normally involve users who think out loud while using a system and an evaluator...... who observes the users’ behavior and listens in on their thoughts. This common core of usability tests is illustrated in Figure 1. The possible variations include, for example, whether the users work individually or in pairs, whether the evaluator is in the room with the user or in an adjoining room...

  3. Managing Product Usability: How companies deal with usability in the development of electronic consumer products

    OpenAIRE

    Van Kuijk, J.I.

    2010-01-01

    Problem statement: Even though there is a large amount of methods for user-centred design, the usability of electronic consumer products (e.g., portable music players, washing machines and mobile phones) is under pressure. Usability is the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use. That the usability of electronic consumer products is under pressure is attributed to an incre...

  4. Universally-Usable Interactive Electronic Physics Instructional And Educational Materials

    Science.gov (United States)

    Gardner, John

    2000-03-01

    Recent developments of technologies that promote full accessibility of electronic information by future generations of people with print disabilities will be described. ("Print disabilities" include low vision, blindness, and dyslexia.) The guiding philosophy of these developments is that information should be created and transmitted in a form that is as display-independent as possible, and that the user should have maximum freedom over how that information is to be displayed. This philosophy leads to maximum usability by everybody and is, in the long run, the only way to assure truly equal access. Research efforts to be described include access to mathematics and scientific notation and to graphs, tables, charts, diagrams, and general object-oriented graphics.

  5. A usability evaluation of the prototype Afrikaanse idiome-woordeboek

    African Journals Online (AJOL)

    When digital tools are developed it is important to consider the usability of the tool. Usability evaluation was done on the Afrikaanse idiome-woordeboek to determine with what success it can be used. Discount usability methods, viz. heuristic evaluation and usability testing were used. This article reports on the findings from ...

  6. Empirical usability testing in a component-based environment : improving test efficiency with component-specific usability measures

    NARCIS (Netherlands)

    Brinkman, W.P.; Haakma, R.; Bouwhuis, D.G.; Bastide, R.; Palanque, P.; Roth, J.

    2005-01-01

    This paper addresses the issue of usability testing in a component-based software engineering environment, specifically measuring the usability of different versions of a component in a more powerful manner than other, more holistic, usability methods. Three component-specific usability measures are

  7. PERBANDINGAN METODE EVALUASI USABILITY (STUDI KASUS : PENGGUNAAN PERANGKAT SMARTPHONE)

    OpenAIRE

    Hendradewa, Andrie Pasca

    2017-01-01

    Usability is a key factor that determine success of a product or interactive system, like smartphone. The increasing use of smartphone and its rapid technology development, requires usability evaluation method that is more accurate and effective to found usability problem, so it can be used for product improvement in development process. This study suggests a usability evaluation method that is most effective to identify problem in smartphone usage. Three usability evaluation methods that com...

  8. Managing Product Usability : How companies deal with usability in the development of electronic consumer products

    NARCIS (Netherlands)

    Van Kuijk, J.I.

    2010-01-01

    Problem statement: Even though there is a large amount of methods for user-centred design, the usability of electronic consumer products (e.g., portable music players, washing machines and mobile phones) is under pressure. Usability is the extent to which a product can be used by specified users to

  9. From Usability Engineering to Evidence-based Usability in Health IT

    NARCIS (Netherlands)

    Marcilly, Romaric; Peute, Linda; Beuscart-Zephir, Marie-Catherine

    2016-01-01

    Usability is a critical factor in the acceptance, safe use, and success of health IT. The User-Centred Design process is widely promoted to improve usability. However, this traditional case by case approach that is rooted in the sound understanding of users' needs is not sufficient to improve

  10. Usability evaluation of healthcare information systems: comparison of methods and classification of usability problems

    NARCIS (Netherlands)

    Khajouei, R.

    2011-01-01

    In ziekenhuizen wordt steeds meer gebruik gemaakt van informatiesystemen, maar de usability laat vaak te wensen over. Reza Khajouei testte twee methodes om de usability te beoordelen. Hij constateert dat beide methoden ongeveer evenveel, maar verschillende problemen aan het licht brengen. Uit een

  11. Usability Evaluation of Public Web Mapping Sites

    Science.gov (United States)

    Wang, C.

    2014-04-01

    Web mapping sites are interactive maps that are accessed via Webpages. With the rapid development of Internet and Geographic Information System (GIS) field, public web mapping sites are not foreign to people. Nowadays, people use these web mapping sites for various reasons, in that increasing maps and related map services of web mapping sites are freely available for end users. Thus, increased users of web mapping sites led to more usability studies. Usability Engineering (UE), for instance, is an approach for analyzing and improving the usability of websites through examining and evaluating an interface. In this research, UE method was employed to explore usability problems of four public web mapping sites, analyze the problems quantitatively and provide guidelines for future design based on the test results. Firstly, the development progress for usability studies were described, and simultaneously several usability evaluation methods such as Usability Engineering (UE), User-Centered Design (UCD) and Human-Computer Interaction (HCI) were generally introduced. Then the method and procedure of experiments for the usability test were presented in detail. In this usability evaluation experiment, four public web mapping sites (Google Maps, Bing maps, Mapquest, Yahoo Maps) were chosen as the testing websites. And 42 people, who having different GIS skills (test users or experts), gender (male or female), age and nationality, participated in this test to complete the several test tasks in different teams. The test comprised three parts: a pretest background information questionnaire, several test tasks for quantitative statistics and progress analysis, and a posttest questionnaire. The pretest and posttest questionnaires focused on gaining the verbal explanation of their actions qualitatively. And the design for test tasks targeted at gathering quantitative data for the errors and problems of the websites. Then, the results mainly from the test part were analyzed. The

  12. Approximate maximum parsimony and ancestral maximum likelihood.

    Science.gov (United States)

    Alon, Noga; Chor, Benny; Pardi, Fabio; Rapoport, Anat

    2010-01-01

    We explore the maximum parsimony (MP) and ancestral maximum likelihood (AML) criteria in phylogenetic tree reconstruction. Both problems are NP-hard, so we seek approximate solutions. We formulate the two problems as Steiner tree problems under appropriate distances. The gist of our approach is the succinct characterization of Steiner trees for a small number of leaves for the two distances. This enables the use of known Steiner tree approximation algorithms. The approach leads to a 16/9 approximation ratio for AML and asymptotically to a 1.55 approximation ratio for MP.

  13. Educational software usability: Artifact or Design?

    Science.gov (United States)

    Van Nuland, Sonya E; Eagleson, Roy; Rogers, Kem A

    2017-03-01

    Online educational technologies and e-learning tools are providing new opportunities for students to learn worldwide, and they continue to play an important role in anatomical sciences education. Yet, as we shift to teaching online, particularly within the anatomical sciences, it has become apparent that e-learning tool success is based on more than just user satisfaction and preliminary learning outcomes-rather it is a multidimensional construct that should be addressed from an integrated perspective. The efficiency, effectiveness and satisfaction with which a user can navigate an e-learning tool is known as usability, and represents a construct which we propose can be used to quantitatively evaluate e-learning tool success. To assess the usability of an e-learning tool, usability testing should be employed during the design and development phases (i.e., prior to its release to users) as well as during its delivery (i.e., following its release to users). However, both the commercial educational software industry and individual academic developers in the anatomical sciences have overlooked the added value of additional usability testing. Reducing learner frustration and anxiety during e-learning tool use is essential in ensuring e-learning tool success, and will require a commitment on the part of the developers to engage in usability testing during all stages of an e-learning tool's life cycle. Anat Sci Educ 10: 190-199. © 2016 American Association of Anatomists. © 2016 American Association of Anatomists.

  14. Mobile Usability Testing in Healthcare: Methodological Approaches.

    Science.gov (United States)

    Borycki, Elizabeth M; Monkman, Helen; Griffith, Janessa; Kushniruk, Andre W

    2015-01-01

    The use of mobile devices and healthcare applications is increasing exponentially worldwide. This has lead to the need for the healthcare industry to develop a better understanding of the impact of the usability of mobile software and hardware upon consumer and health professional adoption and use of these technologies. There are many methodological approaches that can be employed in conducting usability evaluation of mobile technologies. More obtrusive approaches to collecting study data may lead to changes in study participant behaviour, leading to study results that are less consistent with how the technologies will be used in the real-world. Alternatively, less obstrusive methods used in evaluating the usability of mobile software and hardware in-situ and laboratory settings can lead to less detailed information being collected about how an individual interacts with both the software and hardware. In this paper we review and discuss several innovative mobile usability evaluation methods on a contiuum from least to most obtrusive and their effects on the quality of the usability data collected. The strengths and limitations of methods are also discussed.

  15. Maximum permissible dose

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    This chapter presents a historic overview of the establishment of radiation guidelines by various national and international agencies. The use of maximum permissible dose and maximum permissible body burden limits to derive working standards is discussed

  16. UX Professionals’ Definitions of Usability and UX

    DEFF Research Database (Denmark)

    Rajanen, Dorina; Clemmensen, Torkil; Iivari, Netta

    2017-01-01

    This paper examines the views of user experience (UX) professionals on the definitions of usability and UX, and compares the findings between countries and within different socio-cultural groups. A mixed-method analysis was employed on data gathered on 422 professionals through a survey in Turkey......, Finland, Denmark, France, and Malaysia. Usability appears to be an established concept, respondents across all countries agreeing on the importance of the ISO 9241-11 definition. There is also a tendency that UX professionals attach organizational perspective to usability. UX professionals diverge when...... defining UX, and there are systematic differences related to socio-cultural conditions. UX professionals in Finland and France incline more towards the definition highlighting the experiential qualities, when compared to Turkey and Malaysia that incline towards the definition reflecting the ease of use...

  17. Usability Problem Identification in Culturally Diverse Settings

    DEFF Research Database (Denmark)

    Clemmensen, Torkil

    2012-01-01

    There are indications that established methods for evaluating information system usability that have been developed for use in, e.g. Europe or the USA, fail to give reliable results in countries such as India, China or Malaysia. This paper presents the theoretical background, related work...... and a definition of culture that should be useful for studies of multiple-country usability testing. This includes a discussion of cultural fit and the consequences of cultural (in)consistencies between stakeholders in system development and use. As an illustrative example of the kind of academic research...... that needs to be done, a pilot study is described. The pilot study exemplifies themes to explore, who should be participants and where should the study be done, how to find examples of multiple-country usability testing, how to collect data and how to analyse that data and what kind of results and discussion...

  18. Game usability advancing the player experience

    CERN Document Server

    Isbister, Katherine

    2008-01-01

    I. What is usability and why should I care?A. Overview chapter Isbister and Schaffer (Editors)Introduces key concepts and positions book for primary audiences: game developers andstudents aspiring to work in game development. Addresses key concerns that developersmay have about adopting usability, and sets a broad road map of what is to come in thebook.B. Interview with Tobi Saulnier of 1st PlayableA discussion with the CEO of a small game studio about why and how she uses usabilitytechniques in her development.C. Interview with Don Norman of Nielsen Norman groupA discussion with one of the pr

  19. On the Usability of Spoken Dialogue Systems

    DEFF Research Database (Denmark)

    Larsen, Lars Bo

     This work is centred on the methods and problems associated with defining and measuring the usability of Spoken Dialogue Systems (SDS). The starting point is the fact that speech based interfaces has several times during the last 20 years fallen short of the high expectations and predictions held...... by industry, researchers and analysts. Several studies in the literature of SDS indicate that this can be ascribed to a lack of attention from the speech technology community towards the usability of such systems. The experimental results presented in this work are based on a field trial with the OVID home...

  20. MATHEMATICAL MODEL FOR SOFTWARE USABILITY AUTOMATED EVALUATION AND ASSURANCE

    Directory of Open Access Journals (Sweden)

    І. Гученко

    2011-04-01

    Full Text Available The subject of the research is software usability and the aim is construction of mathematicalmodel of estimation and providing of the set level of usability. Methodology of structural analysis,methods of multicriterion optimization and theory of making decision, method of convolution,scientific methods of analysis and analogies is used in the research. The result of executed work isthe model for software usability automated evaluation and assurance that allows not only toestimate the current level of usability during every iteration of agile development but also tomanage the usability of created software products. Results can be used for the construction ofautomated support systems of management the software usability.

  1. The Usability Expert’s Fear of Agility

    DEFF Research Database (Denmark)

    Nielsen, Lene; Madsen, Sabine

    2012-01-01

    This paper contributes to the HCI literature on usability practice with insights about the empirical challenges and global emerging practices caused by the advent of agile software development (ASD). In the paper we report from a worldwide study involving 12 usability professionals from 12...... different countries. The findings show that the usability professionals share a forced development and innovation in their practice that stem from their clients’ adoption and use of ASD methods. The ASD methods challenge the way usability testing is performed, the abilities of the usability expert......, the usability deliverables, and the experts’ assumptions about the importance of validity....

  2. A Cross-Cultural Study of How Usability Professionals Experience the Usability of Everyday Systems

    DEFF Research Database (Denmark)

    Jiang, Y.; Sun, X.; Li, H.

    2009-01-01

    in the study, their understanding of fun systems differs across cultural backgrounds. Also, easy-to-use and useful systems are perceived as being similar or different depending on the usability professional’s cultural background. Most other cross-cultural differences relate to categories of construct......Culture influences many aspects of the design and use of computer systems; understanding better this influence on their own thinking may benefit usability professionals who do cross-cultural usability work. Using Kelly’s notion of personal constructs, we focus on one mediator of culture: how...

  3. Applying usability heuristics to radiotherapy systems

    International Nuclear Information System (INIS)

    Chan, Alvita J.; Islam, Mohammad K.; Rosewall, Tara; Jaffray, David A.; Easty, Anthony C.; Cafazzo, Joseph A.

    2012-01-01

    Background and purpose: Heuristic evaluations have been used to evaluate safety of medical devices by identifying and assessing usability issues. Since radiotherapy treatment delivery systems often consist of multiple complex user-interfaces, a heuristic evaluation was conducted to assess the potential safety issues of such a system. Material and methods: A heuristic evaluation was conducted to evaluate the treatment delivery system at Princess Margaret Hospital (Toronto, Canada). Two independent evaluators identified usability issues with the user-interfaces and rated the severity of each issue. Results: The evaluators identified 75 usability issues in total. Eighteen of them were rated as high severity, indicating the potential to have a major impact on patient safety. A majority of issues were found on the record and verify system, and many were associated with the patient setup process. While the hospital has processes in place to ensure patient safety, recommendations were developed to further mitigate the risks of potential consequences. Conclusions: Heuristic evaluation is an efficient and inexpensive method that can be successfully applied to radiotherapy delivery systems to identify usability issues and improve patient safety. Although this study was conducted only at one site, the findings may have broad implications for the design of these systems.

  4. Usability Testing of Two Ambulatory EHR Navigators.

    Science.gov (United States)

    Hultman, Gretchen; Marquard, Jenna; Arsoniadis, Elliot; Mink, Pamela; Rizvi, Rubina; Ramer, Tim; Khairat, Saif; Fickau, Keri; Melton, Genevieve B

    2016-01-01

    Despite widespread electronic health record (EHR) adoption, poor EHR system usability continues to be a significant barrier to effective system use for end users. One key to addressing usability problems is to employ user testing and user-centered design. To understand if redesigning an EHR-based navigation tool with clinician input improved user performance and satisfaction. A usability evaluation was conducted to compare two versions of a redesigned ambulatory navigator. Participants completed tasks for five patient cases using the navigators, while employing a think-aloud protocol. The tasks were based on Meaningful Use (MU) requirements. The version of navigator did not affect perceived workload, and time to complete tasks was longer in the redesigned navigator. A relatively small portion of navigator content was used to complete the MU-related tasks, though navigation patterns were highly variable across participants for both navigators. Preferences for EHR navigation structures appeared to be individualized. This study demonstrates the importance of EHR usability assessments to evaluate group and individual performance of different interfaces and preferences for each design.

  5. Factors Affecting Faculty Web Portal Usability

    Science.gov (United States)

    Bringula, Rex P.; Basa, Roselle S.

    2011-01-01

    The study investigated the factors that might significantly affect web portal usability. Results of the study were intended to serve as inputs for faculty web portal development of the University of the East-Manila. Descriptive statistics utilized questionnaire data from 82 faculty members. The data showed that most of the respondents were…

  6. Usability Evaluation Method for Agile Software Development

    Directory of Open Access Journals (Sweden)

    Saad Masood Butt

    2015-02-01

    Full Text Available Agile methods are the best fit for tremendously growing software industry due to its flexible and dynamic nature. But the software developed using agile methods do meet the usability standards? To answer this question we can see that majority of agile software development projects currently involve interactive user interface designs, which can only be possible by following User Centered Design (UCD in agile methods. The question here is, how to integrate UCD with agile models. Both Agile models and UCD are iterative in nature but agile models focus on coding and development of software; whereas, UCD focuses on user interface of the software. Similarly, both of them have testing features where the agile model involves automated tested code while UCD involves an expert or a user to test the user interface. In this paper, a new agile usability model is proposed and the evaluation is of the proposed model is presented by practically implementing it in three real life projects. . Key results from these projects clearly show: the proposed agile model incorporates usability evaluation methods, improves the relationship between usability experts to work with agile software experts; in addition, allows agile developers to incorporate the result from UCD into subsequent interactions.

  7. Usability: A Teaching and School Service Project

    Science.gov (United States)

    Snyder, Johnny

    2009-01-01

    Your next usability project could be waiting for you in the college library, registration office, or online admissions process that your college or university utilizes in their daily transactions. As an added bonus, these exercises supplement the IS2002 curriculum model, benefit the instructor's institution, build inter-departmental collaboration,…

  8. Optimizing Usability Studies by Complementary Evaluation Methods

    NARCIS (Netherlands)

    Schmettow, Martin; Bach, Cedric; Scapin, Dominique

    2014-01-01

    This paper examines combinations of complementary evaluation methods as a strategy for efficient usability problem discovery. A data set from an earlier study is re-analyzed, involving three evaluation methods applied to two virtual environment applications. Results of a mixed-effects logistic

  9. Useful to Usable (U2U): Transforming climate information into usable tools to support Midwestern agricultural production

    Science.gov (United States)

    Prokopy, L. S.; Widhalm, M.

    2014-12-01

    There is a close connection between weather and climate patterns and successful agricultural production. Therefore, incorporating climate information into farm management is likely to reduce the risk of economic losses and increase profitability. While weather and climate information is becoming ever more abundant and accessible, the use of such information in the agricultural community remains limited. Useful to Usable (U2U): Transforming Climate Variability and Change Information for Cereal Crop Producers is a USDA-NIFA funded research and extension project focused on improving the use of climate information for agricultural production in the Midwestern United States by developing user-driven decision tools and training resources. The U2U team is a diverse and uniquely qualified group of climatologists, crop modelers, agronomists, and social scientists from 9 Midwestern universities and two NOAA Regional Climate Centers. Together, we strive to help producers make better long-term plans on what, when and where to plant and also how to manage crops for maximum yields and minimum environmental damage. To ensure relevance and usability of U2U products, our social science team is using a number of techniques including surveys and focus groups to integrate stakeholder interests, needs, and concerns into all aspects of U2U research. It is through this coupling of physical and social science disciplines that we strive to transform existing climate information into actionable knowledge.

  10. Supporting Usability Engineering in Small Software Development Organizations

    DEFF Research Database (Denmark)

    Bornoe, Nis; Stage, Jan

    2013-01-01

    Despite an interest and use of different usability engineering methods small software development organizations find it challenging to implement usability engineering into the software development process. We present the results from a study about usability engineering in practice. Through a series...... of semistructured interviews we want to get an understanding of how usability is implemented into the organizations and how it’s practiced in reality. We found that the developers found it problematic to combine agile software development methods with classic usability engineering methods. A lack of solid usability...... engineering expertise and not least experience seems to be a main obstacle for a successful implementation of usability engineering into current software development practices. They are requesting methods and procedures that fit better with their current practices and strategies to implement usability...

  11. Usability Testing: Too Early? Too Much Talking? Too Many Problems?

    DEFF Research Database (Denmark)

    Hertzum, Morten

    2016-01-01

    Usability testing has evolved in response to a search for tests that are cheap, early, easy, and fast. In addition, it accords with a situational definition of usability, such as the one propounded by ISO. By approaching usability from an organizational perspective, this author argues that usabil......Usability testing has evolved in response to a search for tests that are cheap, early, easy, and fast. In addition, it accords with a situational definition of usability, such as the one propounded by ISO. By approaching usability from an organizational perspective, this author argues...... that usability should (also) be evaluated late, that usability professionals should be wary of thinking aloud, and that they should focus more on effects achievement than problem detection....

  12. On the assessment of usability testing methods for children

    NARCIS (Netherlands)

    Markopoulos, P.; Bekker, M.M.

    2003-01-01

    The paper motivates the need to acquire methodological knowledge for involving children as test users in usability testing. It introduces a methodological framework for delineating comparative assessments of usability testing methods for children participants. This framework consists in three

  13. Does Usability Matter? An Analysis of the Impact of Usability on Technology Acceptance in ERP Settings

    Directory of Open Access Journals (Sweden)

    Brenda M Scholtz

    2016-11-01

    Full Text Available Though the field of management information systems, as a sector and a discipline, is the inventor of many guidelines and models, it appears to be a slow runner on practical implications of interface usability. This usability can influence end users’ attitude and behavior to use IT. The purpose of this paper was to examine the interface usability of a popular Enterprise Resource Planning (ERP software system, SAP, and to identify related issues and implications to the Technology Acceptance Model (TAM. A survey was conducted of 112 SAP ERP users from an organization in the heavy metal industry in Bangladesh. The partial least squares technique was used to analyze the survey data. The survey findings empirically confirmed that interface usability has a significant impact on users’ perceptions of usefulness and ease of use which ultimately affects attitudes and intention to use the ERP software. The research model extends the TAM by incorporating three criteria of interface usability. It is the first known study to investigate usability criteria as an extension of TAM.

  14. Toward more usable electronic voting: testing the usability of a smartphone voting system.

    Science.gov (United States)

    Campbell, Bryan A; Tossell, Chad C; Byrne, Michael D; Kortum, Philip

    2014-08-01

    The goal of this research was to assess the usability of a voting system designed for smart-phones. Smartphones offer remote participation in elections through the use of pervasive technology. Voting on these devices could, among other benefits, increase voter participation while allowing voters to use familiar technology. However, the usability of these systems has not been assessed. A mobile voting system optimized for use on a smartphone was designed and tested against traditional voting platforms for usability. There were no reliable differences between the smartphone-based system and other voting methods in efficiency and perceived usability. More important, though, smartphone owners committed fewer errors on the mobile voting system than on the traditional voting systems. Even with the known limitations of small mobile platforms in both displays and controls, a carefully designed system can provide a usable voting method. Much of the concern about mobile voting is in the area of security; therefore, although these results are promising, security concerns and usability issues arising from mitigating them must be strongly considered. The results of this experiment may help to inform current and future election and public policy officials about the benefits of allowing voters to vote with familiar hardware.

  15. Usability Evaluation of a Web-Based Learning System

    Science.gov (United States)

    Nguyen, Thao

    2012-01-01

    The paper proposes a contingent, learner-centred usability evaluation method and a prototype tool of such systems. This is a new usability evaluation method for web-based learning systems using a set of empirically-supported usability factors and can be done effectively with limited resources. During the evaluation process, the method allows for…

  16. Usability and Gratifications--Towards a Website Analysis Model.

    Science.gov (United States)

    Bunz, Ulla K.

    This paper discusses Web site usability issues. Specifically, it assumes that the usability of a Web site depends more on the perception of the user than on the objectively assessable usability criteria of the Web site. Two pilot studies, based on theoretical notions of uses and gratifications theory and similar theories, are presented. In the…

  17. Barefooted Usability Evaluation: Addressing the Mindset, Resources and Competences

    OpenAIRE

    Bruun , Anders

    2011-01-01

    Part 1: Long and Short Papers; International audience; Lack of usability specialists, high resource requirements and developer mindsets are three considerable barriers for introducing usability engineering into software companies. This Ph.D. project explores the effect of letting software developers and end users apply usability engineering methods instead of a specialist, a solution which may reduce the barriers.

  18. Assessing Library Instruction through Web Usability and Vocabulary Studies

    Science.gov (United States)

    Castonguay, Remi

    2008-01-01

    Can we use the methods of Web usability testing to learn about library instruction? This article is among the first in the field trying to establish a link between usability and instruction. The author discusses useful insights that Web usability can bring to our pedagogy as well as to the efficiency of library instruction. The result of a Web…

  19. Building a Remote Usability Testing Body of Knowledge (RUTBOK)

    DEFF Research Database (Denmark)

    Lizano, Fulvio; Stage, Jan

    2012-01-01

    Remote Usability Testing (RUT) is an alternative method of usability evaluations. The main aim of RUT is the reduction of costs in the usability evaluation process. Since middle of the 90s RUT, has emerged as a technique which seems as is gaining maturity across the time. In general any discipline...

  20. Methods of Usability Testing in Libraries Web Sites

    Directory of Open Access Journals (Sweden)

    Eman Fawzy

    2006-03-01

    Full Text Available A Study about libraries' web sites evaluation, that is the Usability, the study talking about methods of usability testing and define it, and its important in web sites evaluation, then details the methods of usability: questionnaire, core groups, testing experimental model, cards arrangement, and composed evaluation.

  1. On Maximum Entropy and Inference

    Directory of Open Access Journals (Sweden)

    Luigi Gresele

    2017-11-01

    Full Text Available Maximum entropy is a powerful concept that entails a sharp separation between relevant and irrelevant variables. It is typically invoked in inference, once an assumption is made on what the relevant variables are, in order to estimate a model from data, that affords predictions on all other (dependent variables. Conversely, maximum entropy can be invoked to retrieve the relevant variables (sufficient statistics directly from the data, once a model is identified by Bayesian model selection. We explore this approach in the case of spin models with interactions of arbitrary order, and we discuss how relevant interactions can be inferred. In this perspective, the dimensionality of the inference problem is not set by the number of parameters in the model, but by the frequency distribution of the data. We illustrate the method showing its ability to recover the correct model in a few prototype cases and discuss its application on a real dataset.

  2. Maximum Acceleration Recording Circuit

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1995-01-01

    Coarsely digitized maximum levels recorded in blown fuses. Circuit feeds power to accelerometer and makes nonvolatile record of maximum level to which output of accelerometer rises during measurement interval. In comparison with inertia-type single-preset-trip-point mechanical maximum-acceleration-recording devices, circuit weighs less, occupies less space, and records accelerations within narrower bands of uncertainty. In comparison with prior electronic data-acquisition systems designed for same purpose, circuit simpler, less bulky, consumes less power, costs and analysis of data recorded in magnetic or electronic memory devices. Circuit used, for example, to record accelerations to which commodities subjected during transportation on trucks.

  3. Usability: managing facilities for social outcomes

    DEFF Research Database (Denmark)

    Alexander, Keith; Blakstad, Siri; Hansen, Geir

    2013-01-01

    The paper argues for the development of usability concepts, methodologies and tools, in considering the effects of the built environment from a user, organisational and community perspective, in order to have a positive influence on social outcomes. Since it was formed over ten years ago, the CIB W......111 on Usability has been exploring concepts, methods and tools, developed in the evaluation of all kinds of consumer products, applied to the built environment. In the most recent phase of this work, conducted over the past three years, an international network of partners has collaborated to focus...... properties of a workplace, they could better manage and design the facilities for improved social outcomes. Interpretation and analysis of the built environment (and support services) based on how it is socially constructed will enable integration of organisational use and the facilities provided to arrive...

  4. A usability evaluation of Lazada mobile application

    Science.gov (United States)

    Hussain, Azham; Mkpojiogu, Emmanuel O. C.; Jamaludin, Nur Hafiza; Moh, Somia T. L.

    2017-10-01

    This paper reports on a usability evaluation of Lazada mobile application, an online shopping app for mobile devices. The evaluation was conducted using 12 users of ages 18 to 24. Seven (7) were expert users and the other 5 were novice users. The study objectives were to evaluate the perceived effectiveness, efficiency and satisfaction of the mobile application. The result provides a positive feedback and shows that the mobile shopping app is effective, efficient, and satisfying as perceived by the study participants. However, there are some observed usability issues with the main menu and the payment method that necessitates improvements to increase the application's effectiveness, efficiency and satisfaction. The suggested improvements include: 1) the main menu should be capitalized and place on the left side of mobile app and 2) payment method tutorial should be included as a hyperlink in the payment method page. This observation will be helpful to the owners of the application in future version development of the app.

  5. Safeguarding nuclear weapon: Usable materials in Russia

    International Nuclear Information System (INIS)

    Cochran, T.

    1998-01-01

    Both the United States and Russia are retaining as strategic reserves more plutonium and HEU for potential reuse as weapons, than is legitimately needed. Both have engaged in discussions and have programs in various stages of development to dispose of excess plutonium and HEU. These fissile material disposition programs will take decades to complete. In the interim there will be, as there is now, hundreds of tons of separated weapon-usable fissile material stored in tens of thousands of transportable canisters, each containing from a few to several tons of kgs of weapon-usable fissile material. This material must be secured against theft and unauthorized use. To have high confidence that the material is secure, one must establish criteria against which the adequacy of the protective systems can be judged. For example, one finds such criteria in US Nuclear Regulatory Commission (USNRC) regulations for the protection of special nuclear materials

  6. Estimating Sample Size for Usability Testing

    Directory of Open Access Journals (Sweden)

    Alex Cazañas

    2017-02-01

    Full Text Available One strategy used to assure that an interface meets user requirements is to conduct usability testing. When conducting such testing one of the unknowns is sample size. Since extensive testing is costly, minimizing the number of participants can contribute greatly to successful resource management of a project. Even though a significant number of models have been proposed to estimate sample size in usability testing, there is still not consensus on the optimal size. Several studies claim that 3 to 5 users suffice to uncover 80% of problems in a software interface. However, many other studies challenge this assertion. This study analyzed data collected from the user testing of a web application to verify the rule of thumb, commonly known as the “magic number 5”. The outcomes of the analysis showed that the 5-user rule significantly underestimates the required sample size to achieve reasonable levels of problem detection.

  7. Maximum Quantum Entropy Method

    OpenAIRE

    Sim, Jae-Hoon; Han, Myung Joon

    2018-01-01

    Maximum entropy method for analytic continuation is extended by introducing quantum relative entropy. This new method is formulated in terms of matrix-valued functions and therefore invariant under arbitrary unitary transformation of input matrix. As a result, the continuation of off-diagonal elements becomes straightforward. Without introducing any further ambiguity, the Bayesian probabilistic interpretation is maintained just as in the conventional maximum entropy method. The applications o...

  8. Maximum power demand cost

    International Nuclear Information System (INIS)

    Biondi, L.

    1998-01-01

    The charging for a service is a supplier's remuneration for the expenses incurred in providing it. There are currently two charges for electricity: consumption and maximum demand. While no problem arises about the former, the issue is more complicated for the latter and the analysis in this article tends to show that the annual charge for maximum demand arbitrarily discriminates among consumer groups, to the disadvantage of some [it

  9. Integrated System Validation Usability Questionnaire: Computerized Procedures

    International Nuclear Information System (INIS)

    Garcés, Ma. I.; Torralba, B.

    2015-01-01

    The Research and Development (R&D) project on “Theoretical and Methodological Approaches to Integrated System Validation of Control Rooms, 2014-2015”, in which the research activities described in this report are framed, has two main objectives: to develop the items for an usability methodology conceived as a part of the measurement framework for performance-based control room evaluation that the OECD Halden Reactor Project will test in the experiments planned for 2015; and the statistical analysis of the data generated in the experimental activities of the Halden Man-Machine Laboratory (HAMMLAB) facility, with previous usability questionnaires, in 2010 and 2011. In this report, the procedure designed to meet the first goal of the project is described, in particular, the process followed to identify the items related to operating procedures, both computer and paper-based, one of the elements to be included in the usability questionnaire. Three phases are performed, in the first one, the approaches developed by the United States Nuclear Regulatory Commission, NRC, are reviewed, the models used by the nuclear industry and their technical support organizations, mainly, the Electric Power Research Institute, EPRI, are analyzed, and scientist advances are also explored. In the remaining stages, general and specific guidelines for computerized and paper-based procedures are compared and criteria for the preliminary selection of the items that should be incorporated into the usability questionnaire are defined. This proposal will be reviewed and adapted by the Halden Reactor Project to the design of the specific experiments performed in HAMLAB.

  10. Commercial versus in-situ usability testing of healthcare information systems: towards "public" usability testing in healthcare organizations.

    Science.gov (United States)

    Kushniruk, Andre W; Borycki, Elizabeth M; Kannry, Joseph

    2013-01-01

    The need for improved usability in healthcare IT has been widely recognized. In addition, methods from usability engineering, including usability testing and usability inspection have received greater attention. Many vendors of healthcare software are now employing usability testing methods in the design and development of their products. However, despite this, the usability of healthcare IT is still considered to be problematic and many healthcare organizations that have purchased systems that have been tested at vendor testing sites are still reporting a range of usability and safety issues. In this paper we explore the distinction between commercial usability testing (conducted at centralized vendor usability laboratories and limited beta test sites) and usability testing that is carried out locally within healthcare organizations that have purchased vendor systems and products (i.e. public "in-situ" usability testing). In this paper it will be argued that both types of testing (i.e. commercial vendor-based testing) and in-situ testing are needed to ensure system usability and safety.

  11. A Longitudinal Study of Usability in Health Care

    DEFF Research Database (Denmark)

    Kjeldskov, Jesper; Skov, Mikael B.; Stage, Jan

    2010-01-01

    We report from a longitudinal laboratory-based usability evaluation of a health care information system. The purpose of the study was to inquire into the nature of usability problems experienced by novice and expert users, and to see to what extend usability problems of a health care information...... system may or may not disappear over time, as the nurses get more familiar with it-if time heals poor design? As our method for studying this, we conducted a longitudinal study with two key studies. A usability evaluation was conducted with novice users when an electronic patient record system was being......, we discuss implications for evaluating usability in health care....

  12. Active Involvement of Software Developers in Usability Engineering

    DEFF Research Database (Denmark)

    Bornoe, Nis; Stage, Jan

    2017-01-01

    The essence of usability evaluations is to produce feedback that supports the downstream utility so the interaction design can be improved and problems can be fixed. In practice, software development organizations experience several obstacles for conducting usability engineering. One suggested...... approach is to train and involve developers in all phases of usability activities from evaluations, to problem reporting, and making redesign proposals. Only limited work has previously investigated the impact of actively involving developers in usability engineering. In this paper, we present two small......, and problem fixing. At the organizational level, we found that the attitude towards and understanding of the role of usability engineering improved....

  13. Towards Usable E-Health. A Systematic Review of Usability Questionnaires.

    Science.gov (United States)

    Sousa, Vanessa E C; Dunn Lopez, Karen

    2017-05-10

    The use of e-health can lead to several positive outcomes. However, the potential for e-health to improve healthcare is partially dependent on its ease of use. In order to determine the usability for any technology, rigorously developed and appropriate measures must be chosen. To identify psychometrically tested questionnaires that measure usability of e-health tools, and to appraise their generalizability, attributes coverage, and quality. We conducted a systematic review of studies that measured usability of e-health tools using four databases (Scopus, PubMed, CINAHL, and HAPI). Non-primary research, studies that did not report measures, studies with children or people with cognitive limitations, and studies about assistive devices or medical equipment were systematically excluded. Two authors independently extracted information including: questionnaire name, number of questions, scoring method, item generation, and psychometrics using a data extraction tool with pre-established categories and a quality appraisal scoring table. Using a broad search strategy, 5,558 potentially relevant papers were identified. After removing duplicates and applying exclusion criteria, 35 articles remained that used 15 unique questionnaires. From the 15 questionnaires, only 5 were general enough to be used across studies. Usability attributes covered by the questionnaires were: learnability (15), efficiency (12), and satisfaction (11). Memorability (1) was the least covered attribute. Quality appraisal showed that face/content (14) and construct (7) validity were the most frequent types of validity assessed. All questionnaires reported reliability measurement. Some questionnaires scored low in the quality appraisal for the following reasons: limited validity testing (7), small sample size (3), no reporting of user centeredness (9) or feasibility estimates of time, effort, and expense (7). Existing questionnaires provide a foundation for research on e-health usability. However

  14. Maximum likely scale estimation

    DEFF Research Database (Denmark)

    Loog, Marco; Pedersen, Kim Steenstrup; Markussen, Bo

    2005-01-01

    A maximum likelihood local scale estimation principle is presented. An actual implementation of the estimation principle uses second order moments of multiple measurements at a fixed location in the image. These measurements consist of Gaussian derivatives possibly taken at several scales and/or ...

  15. Robust Maximum Association Estimators

    NARCIS (Netherlands)

    A. Alfons (Andreas); C. Croux (Christophe); P. Filzmoser (Peter)

    2017-01-01

    textabstractThe maximum association between two multivariate variables X and Y is defined as the maximal value that a bivariate association measure between one-dimensional projections αX and αY can attain. Taking the Pearson correlation as projection index results in the first canonical correlation

  16. Lessons from an Educational Game Usability Evaluation

    Directory of Open Access Journals (Sweden)

    Gabriela Trindade Perry

    2012-04-01

    Full Text Available In this paper, we present the results of a usability evaluation for Xenubi, a cell phone game about the periodic table. We describe and discuss the issues that we faced during the evaluation, which took place in a state high school. These issues are related to conflicts between the data that were gathered through video recordings and through a questionnaire. We also point to the poor performance of the game mechanics during the evaluation. This result was unexpected because the game had an excellent performance in the pilot test. Possible causes for these differences are discussed.

  17. Usability analysis of industrial cooking equipment.

    Science.gov (United States)

    Calado, Alexana Vilar Soares; Soares, Marcelo Márcio

    2012-01-01

    This paper refers to the comparative study of the equipment used for cooking in commercial of kitchens restaurants that use the system of traditional cooking and those ones which use the system called smart cooking (combination oven). The study investigates the usability issues concerning to the two systems, analyzing comparatively the aspects related to anthropometry, dimensional variables, the use of the product and also the product safety, as well as issues of information related to operation of the new concepts of cooking in intelligent systems.

  18. Usability of synchronization for cognitive modeling

    International Nuclear Information System (INIS)

    Diebner, Hans H.; Grond, Florian

    2005-01-01

    We discuss the synchronization features of a previously introduced adaptive system for dynamics recognition in more detail. We investigate the usability of synchronization for modeling and parameter estimations. It is pointed out inhowfar the adaptive system based on synchronization can become a powerful tool in modeling. The adaptive system can store modules of pre-adapted dynamics and is potentially capable of undergoing self-modification. We compare the stored modules with pre-knowledge that a modeler puts into his or her models. In this sense the adaptive system functions like an expert system

  19. Usability testing of interaction components: taking the message exchange as a measure of usability

    NARCIS (Netherlands)

    Brinkman, W.P.; Haakma, R.; Bouwhuis, D.G.; Jacob, R.J.K.; Limbourg, Q; Vanderdonckt, J.

    2004-01-01

    Component-based Software Engineering (CBSE) is concerned with the development of systems from reusable parts (components), and the development and maintenance of these parts. This study addresses the issue of usability testing in a CBSE environment, and specifically automatically measuring the

  20. Maximum power point tracking

    International Nuclear Information System (INIS)

    Enslin, J.H.R.

    1990-01-01

    A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking can be m ore cost effective, has a higher reliability and can improve the quality of life in remote areas. This paper reports that a high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of 15% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply systems. The advantages at larger temperature variations and larger power rated systems are much higher. Other advantages include optimal sizing and system monitor and control

  1. Usability: Human Research Program - Space Human Factors and Habitability

    Science.gov (United States)

    Sandor, Aniko; Holden, Kritina L.

    2009-01-01

    The Usability project addresses the need for research in the area of metrics and methodologies used in hardware and software usability testing in order to define quantifiable and verifiable usability requirements. A usability test is a human-in-the-loop evaluation where a participant works through a realistic set of representative tasks using the hardware/software under investigation. The purpose of this research is to define metrics and methodologies for measuring and verifying usability in the aerospace domain in accordance with FY09 focus on errors, consistency, and mobility/maneuverability. Usability metrics must be predictive of success with the interfaces, must be easy to obtain and/or calculate, and must meet the intent of current Human Systems Integration Requirements (HSIR). Methodologies must work within the constraints of the aerospace domain, be cost and time efficient, and be able to be applied without extensive specialized training.

  2. Integrating Usability Evaluations into the Software Development Process

    DEFF Research Database (Denmark)

    Lizano, Fulvio

    as relevant and strategic human–computer interaction (HCI) activities in the software development process, there are obstacles that limit the complete, effective and efficient integration of this kind of testing into the software development process. Two main obstacles are the cost of usability evaluations...... and the software developers' resistance to accepting users’ opinions regarding the lack of usability in their software systems. The ‘cost obstacle’ refers to the constraint of conducting usability evaluations in the software process due to the significant amount of resources required by this type of testing. Some......This thesis addresses the integration of usability evaluations into the software development process. The integration here is contextualized in terms of how to include usability evaluation as an activity in the software development lifecycle. Even though usability evaluations are considered...

  3. Usability testing of indonesia tourism promotion website

    Science.gov (United States)

    Yunus, U.; Anindito; Tanuar, E.; Maryani

    2018-03-01

    Indonesian tourism has been viewed as one of the source of foreign exchange, therefore visit Indonesia campaign through Wonderful Indonesia should be given attention. This research aims to test the usability of web http://www.indonesia.travel/en, at the end can give input to the Tourism Ministry of the Republic of Indonesia. The concept used based on usabilitygeek.com which mentions the three main categories for usability testing, i. e. explorative, assessment and comparative with the users are three classes of Communication Department students of Bina Nusantara University with a total of 120 students, however finally only 22 students were elected because of the criteria are the students should be like travelling and access to the tourism website more than 12 times. The methodology used is qualitative descriptive and experiments, with data collection techniques through observation and interviews after participants’ access to the web: Due to their one-on-one nature, interviews enable the observer to ask direct questions to the user and the participants posted their opinion in online discussion forum. The results mentioned that the elements web of Wonderful Indonesia has a high learning ability and memorability but less efficiency and satisfaction, as well as several times errors when used. In conclusion, to maximize about the visit of tourism to Indonesia, this web is only able to learn and impress the visitor, but do not give satisfaction to users.

  4. Business-Intelligence-Systeme im Spannungsfeld zwischen Usability und Sicherheit

    OpenAIRE

    Hinck, Thorsten

    2010-01-01

    Business-Intelligence-Systeme stehen im Spannungsfeld zwischen Usability und Sicherheit. Die Gefahren und Sicherheitsmaßnahmen für Informationssysteme werden ermittelt und ökonomisch in Bezug zur Gebrauchstauglichkeit gesetzt. Es entsteht ein Sicherheitsprofil für Business-Intelligence-Systeme. Business-Intelligence-Systems are in tension between Usability and IT-Security. Risks and safety measures of informationsystems are defined and set in (economic) regard to Usability. A security prof...

  5. Usability evaluation techniques in mobile commerce applications: A systematic review

    Science.gov (United States)

    Hussain, Azham; Mkpojiogu, Emmanuel O. C.

    2016-08-01

    Obviously, there are a number of literatures concerning the usability of mobile commerce (m-commerce) applications and related areas, but they do not adequately provide knowledge about usability techniques used in most of the empirical usability evaluation for m-commerce application. Therefore, this paper is aimed at producing the usability techniques frequently used in the aspect of usability evaluation for m-commerce applications. To achieve the stated objective, systematic literature review was employed. Sixty seven papers were downloaded in usability evaluation for m-commerce and related areas; twenty one most relevant studies were selected for review in order to extract the appropriate information. The results from the review shows that heuristic evaluation, formal test and think aloud methods are the most commonly used methods in m-commerce application in comparison to cognitive walkthrough and the informal test methods. Moreover, most of the studies applied control experiment (33.3% of the total studies); other studies that applied case study for usability evaluation are 14.28%. The results from this paper provide additional knowledge to the usability practitioners and research community for the current state and use of usability techniques in m-commerce application.

  6. A Framework for Usability Evaluation in EHR Procurement.

    Science.gov (United States)

    Tyllinen, Mari; Kaipio, Johanna; Lääveri, Tinja

    2018-01-01

    Usability should be considered already by the procuring organizations when selecting future systems. In this paper, we present a framework for usability evaluation during electronic health record (EHR) system procurement. We describe the objectives of the evaluation, the procedure, selected usability attributes and the evaluation methods to measure them. We also present the emphasis usability had in the selection process. We do not elaborate on the details of the results, the application of methods or gathering of data. Instead we focus on the components of the framework to inform and give an example to other similar procurement projects.

  7. Templates for Cross-Cultural and Culturally Specific Usability Testing

    DEFF Research Database (Denmark)

    Clemmensen, Torkil

    2011-01-01

    The cultural diversity of users of technology challenges our methods for usability testing. This article suggests templates for cross-culturally and culturally specific usability testing, based on studies of usability testing in companies in Mumbai, Beijing, and Copenhagen. Study 1 was a cross...... tests. The result was the construction of templates for usability testing. The culturally specific templates were in Mumbai “user-centered evaluation,” Copenhagen “client-centered evaluation,” and Beijing “evaluator-centered evaluation.” The findings are compared with related research...

  8. Cost-justifying usability an update for the internet age

    CERN Document Server

    Bias, Randolph G; Bias, Randolph G

    2005-01-01

    You just know that an improvement of the user interface will reap rewards, but how do you justify the expense and the labor and the time-guarantee a robust ROI!-ahead of time? How do you decide how much of an investment should be funded? And what is the best way to sell usability to others? In this completely revised and new edition, Randolph G. Bias (University of Texas at Austin, with 25 years' experience as a usability practitioner and manager) and Deborah J. Mayhew (internationally recognized usability consultant and author of two other seminal books including The Usability Enginee

  9. Assessment of Usability Benchmarks: Combining Standardized Scales with Specific Questions

    Directory of Open Access Journals (Sweden)

    Stephanie Bettina Linek

    2011-12-01

    Full Text Available The usability of Web sites and online services is of rising importance. When creating a completely new Web site, qualitative data are adequate for identifying the most usability problems. However, changes of an existing Web site should be evaluated by a quantitative benchmarking process. The proposed paper describes the creation of a questionnaire that allows a quantitative usability benchmarking, i.e. a direct comparison of the different versions of a Web site and an orientation on general standards of usability. The questionnaire is also open for qualitative data. The methodology will be explained by the digital library services of the ZBW.

  10. Development and testing of new upper-limb prosthetic devices: research designs for usability testing.

    Science.gov (United States)

    Resnik, Linda

    2011-01-01

    The purposes of this article are to describe usability testing and introduce designs and methods of usability testing research as it relates to upper-limb prosthetics. This article defines usability, describes usability research, discusses research approaches to and designs for usability testing, and highlights a variety of methodological considerations, including sampling, sample size requirements, and usability metrics. Usability testing is compared with other types of study designs used in prosthetic research.

  11. Maximum entropy methods

    International Nuclear Information System (INIS)

    Ponman, T.J.

    1984-01-01

    For some years now two different expressions have been in use for maximum entropy image restoration and there has been some controversy over which one is appropriate for a given problem. Here two further entropies are presented and it is argued that there is no single correct algorithm. The properties of the four different methods are compared using simple 1D simulations with a view to showing how they can be used together to gain as much information as possible about the original object. (orig.)

  12. The last glacial maximum

    Science.gov (United States)

    Clark, P.U.; Dyke, A.S.; Shakun, J.D.; Carlson, A.E.; Clark, J.; Wohlfarth, B.; Mitrovica, J.X.; Hostetler, S.W.; McCabe, A.M.

    2009-01-01

    We used 5704 14C, 10Be, and 3He ages that span the interval from 10,000 to 50,000 years ago (10 to 50 ka) to constrain the timing of the Last Glacial Maximum (LGM) in terms of global ice-sheet and mountain-glacier extent. Growth of the ice sheets to their maximum positions occurred between 33.0 and 26.5 ka in response to climate forcing from decreases in northern summer insolation, tropical Pacific sea surface temperatures, and atmospheric CO2. Nearly all ice sheets were at their LGM positions from 26.5 ka to 19 to 20 ka, corresponding to minima in these forcings. The onset of Northern Hemisphere deglaciation 19 to 20 ka was induced by an increase in northern summer insolation, providing the source for an abrupt rise in sea level. The onset of deglaciation of the West Antarctic Ice Sheet occurred between 14 and 15 ka, consistent with evidence that this was the primary source for an abrupt rise in sea level ???14.5 ka.

  13. DEVELOPING AND VALIDATION A USABILITY EVALUATION TOOLS FOR DISTANCE EDUCATION WEBSITES: Persian Version

    Directory of Open Access Journals (Sweden)

    Soheila HAFEZI

    2010-07-01

    Full Text Available The web is playing a central role in distance education. The word “usability” is usually synonymous with functionality of the system for the user. Also, usability of a website is defined as something that can be used by a specific group of people to carry out specific objectives in an effective way, with efficiency and satisfaction. There are some useful usability evaluation instruments of websites in other languages. The aim of this study was to develop a Persian instrument to evaluate usability in distance education websites. This study was a methodology research design. According to review literature, the main structure of evaluation instrument for usability designed. It was consisted of forty-eight items divided in 8 domains. Each domain was composed of closed multiple choice questions in which an ordinal scale with three values is used (always, sometimes and never that measures the opinion of the evaluator about the frequency of visiting each item selected in the website. After that, we used face validity method. It refers to what instrument appears superficially to measure. At the final step, we omputed a formal content validity index (CVI across the experts’ ratings of each item’s relevance. The content validity index was measured by set of ten experts, who evaluated each item individually. According to CVI, the final version of instrument was composed of 40 questions divided into 8 domains: Navigation, Functionality, Feedback, Control, Language, Consistency, Error prevention and correction, and Visual clarity.CVI score for each phrase was more than 0.75. According to our findings, this instrument has enough validity to apply in evaluation usability of educational websites of Persian distance education websites. However, instrument reliability can be measured in further study.

  14. Usability Evaluation for Business Intelligence Applications: A User Support Perspective

    Directory of Open Access Journals (Sweden)

    Chrisna Jooste

    2014-08-01

    Full Text Available Business Intelligence (BI applications provide business information to drive decision support. Usability is one of the factors determining the optimal use and eventual benefit derived from BI applications. The documented need for more BI usability research together with the practical necessity for BI evaluation guidelines in the mining industry provides the rationale for this study. The purpose of the study was to investigate the usability evaluation of BI applications in the context of a coal mining organization. The research is guided by the question: How can existing usability criteria be customized to evaluate the usability of BI applications. The research design included user observation, heuristic evaluation and a survey. Based on observations made during user support on a BI application used at a coal mining organization a log of usability issues was compiled. The usability issues extracted from this log was compared and contrasted with general usability criteria from literature to synthesize an initial set of BI usability evaluation criteria. These criteria were used as the basis for a heuristic evaluation of the BI application used at the coal mining organization. The same BI application was also evaluated using the Software Usability Measurement Inventory (SUMI standardized questionnaire. The results from the two evaluations were triangulated and then compared with the BI user issues again to contextualize the findings and synthesize a validated and refined set of criteria. The main contribution of the study is the usability evaluation criteria for BI applications presented as guidelines. These guidelines deviate from existing evaluation guidelines in the emphasis on information architecture, learnability and operability.

  15. Online Biodiversity Resources - Principles for Usability

    Directory of Open Access Journals (Sweden)

    Sophie Neale

    2007-01-01

    Full Text Available Online biodiversity portals and databases enabling access to large volumes of biological information represent a potentially extensive set of resources for a variety of user groups. However, in order for these resources to live up to their promise they need to be both useful and easy to use. We discuss a number of principles for designing systems for usability, examine how these have been applied to the development of online biodiversity resources and compare this with a portal project developed by the Astrophysics community. We highlight a lack of user involvement and formalised requirements analysis by biodiversity projects resulting in a poor understanding of both the users and their tasks. We suggest a change in the way large biodiversity portal projects are structured, that is by providing infrastructure and supporting user groups developing individual interfaces.

  16. Useful and usable alarm systems : recommended properties

    International Nuclear Information System (INIS)

    Veland, Oeystein; Kaarstad, Magnhild; Seim, Lars Aage; Foerdestroemmen, Nils T.

    2001-01-01

    This document describes the result of a study on alarm systems conducted by IFE in Halden. The study was initiated by the Norwegian Petroleum Directorate. The objective was to identify and formulate a set of important properties for useful and usable alarm systems. The study is mainly based on review of the latest international recognised guidelines and standards on alarm systems available at the time of writing, with focus on realistic solutions from research and best practice from different industries. In addition, IFE experiences gathered through specification and design of alarm systems and experimental activities in HAMMLAB and bilateral projects, have been utilized where relevant. The document presents a total of 43 recommendations divided into a number of general recommendations and more detailed recommendations on alarm generation, structuring, prioritisation, presentation and handling. (Author)

  17. Methods and Tools for Ethical Usability

    Science.gov (United States)

    Kavathatzopoulos, Iordanis; Kostrzewa, Agata; Laaksoharju, Mikael

    The objectives of the tutorial are to provide knowledge of basic ethical, psychological and organizational theories that are relevant to consider ethical aspects during design and use of IT systems; knowledge and skills about handling and solving ethical problems in connection with design and use of IT-systems; and skills in using questionnaires, surveys, interviews and the like in connection with software development and IT-use. It contains lectures, workshop and exercises; use of special tools to identify and consider IT ethical issues during planning, construction, installation and use of IT systems; and group exercises where the participants train their ethical skills on IT ethical conflicts and problems. Intended participants are system developers, purchasers, usability experts, academics, HCI teachers.

  18. Enhancing the Usability of Telecare Devices

    Directory of Open Access Journals (Sweden)

    José Manuel Ojel-Jaramillo

    2006-01-01

    Full Text Available Demographic and sociological changes in the last 50 years have forced Western societies to create services to attend to elderly people in their homes, where they can live within familiar environments. Telecare involves a device plugged into a telephonic network that provides access to teams of professionals who can attend to the needs of the elderly in their homes. These devices have been designed according to the principles of universal design, but the great number of erroneous calls to telecare centers point to the necessity of enhancing the usability of the devices. One analysis of the cognitive functioning of elderly people showed that a possible cause of these errors could be the difficulty elderly people have when processing language. In our experiment, we tested the hypothesis that the numbers of errors could be reduced by using icons instead of words in the device interface. The results support this hypothesis.

  19. Maximum Entropy Fundamentals

    Directory of Open Access Journals (Sweden)

    F. Topsøe

    2001-09-01

    Full Text Available Abstract: In its modern formulation, the Maximum Entropy Principle was promoted by E.T. Jaynes, starting in the mid-fifties. The principle dictates that one should look for a distribution, consistent with available information, which maximizes the entropy. However, this principle focuses only on distributions and it appears advantageous to bring information theoretical thinking more prominently into play by also focusing on the "observer" and on coding. This view was brought forward by the second named author in the late seventies and is the view we will follow-up on here. It leads to the consideration of a certain game, the Code Length Game and, via standard game theoretical thinking, to a principle of Game Theoretical Equilibrium. This principle is more basic than the Maximum Entropy Principle in the sense that the search for one type of optimal strategies in the Code Length Game translates directly into the search for distributions with maximum entropy. In the present paper we offer a self-contained and comprehensive treatment of fundamentals of both principles mentioned, based on a study of the Code Length Game. Though new concepts and results are presented, the reading should be instructional and accessible to a rather wide audience, at least if certain mathematical details are left aside at a rst reading. The most frequently studied instance of entropy maximization pertains to the Mean Energy Model which involves a moment constraint related to a given function, here taken to represent "energy". This type of application is very well known from the literature with hundreds of applications pertaining to several different elds and will also here serve as important illustration of the theory. But our approach reaches further, especially regarding the study of continuity properties of the entropy function, and this leads to new results which allow a discussion of models with so-called entropy loss. These results have tempted us to speculate over

  20. Next Gen One Portal Usability Evaluation

    Science.gov (United States)

    Cross, E. V., III; Perera, J. S.; Hanson, A. M.; English, K.; Vu, L.; Amonette, W.

    2018-01-01

    Each exercise device on the International Space Station (ISS) has a unique, customized software system interface with unique layouts / hierarchy, and operational principles that require significant crew training. Furthermore, the software programs are not adaptable and provide no real-time feedback or motivation to enhance the exercise experience and/or prevent injuries. Additionally, the graphical user interfaces (GUI) of these systems present information through multiple layers resulting in difficulty navigating to the desired screens and functions. These limitations of current exercise device GUI's lead to increased crew time spent on initiating, loading, performing exercises, logging data and exiting the system. To address these limitations a Next Generation One Portal (NextGen One Portal) Crew Countermeasure System (CMS) was developed, which utilizes the latest industry guidelines in GUI designs to provide an intuitive ease of use approach (i.e., 80% of the functionality gained within 5-10 minutes of initial use without/limited formal training required). This is accomplished by providing a consistent interface using common software to reduce crew training, increase efficiency & user satisfaction while also reducing development & maintenance costs. Results from the usability evaluations showed the NextGen One Portal UI having greater efficiency, learnability, memorability, usability and overall user experience than the current Advanced Resistive Exercise Device (ARED) UI used by astronauts on ISS. Specifically, the design of the One-Portal UI as an app interface similar to those found on the Apple and Google's App Store, assisted many of the participants in grasping the concepts of the interface with minimum training. Although the NextGen One-Portal UI was shown to be an overall better interface, observations by the test facilitators noted specific exercise tasks appeared to have a significant impact on the NextGen One-Portal UI efficiency. Future updates to

  1. Probable maximum flood control

    International Nuclear Information System (INIS)

    DeGabriele, C.E.; Wu, C.L.

    1991-11-01

    This study proposes preliminary design concepts to protect the waste-handling facilities and all shaft and ramp entries to the underground from the probable maximum flood (PMF) in the current design configuration for the proposed Nevada Nuclear Waste Storage Investigation (NNWSI) repository protection provisions were furnished by the United States Bureau of Reclamation (USSR) or developed from USSR data. Proposed flood protection provisions include site grading, drainage channels, and diversion dikes. Figures are provided to show these proposed flood protection provisions at each area investigated. These areas are the central surface facilities (including the waste-handling building and waste treatment building), tuff ramp portal, waste ramp portal, men-and-materials shaft, emplacement exhaust shaft, and exploratory shafts facility

  2. Introduction to maximum entropy

    International Nuclear Information System (INIS)

    Sivia, D.S.

    1988-01-01

    The maximum entropy (MaxEnt) principle has been successfully used in image reconstruction in a wide variety of fields. We review the need for such methods in data analysis and show, by use of a very simple example, why MaxEnt is to be preferred over other regularizing functions. This leads to a more general interpretation of the MaxEnt method, and its use is illustrated with several different examples. Practical difficulties with non-linear problems still remain, this being highlighted by the notorious phase problem in crystallography. We conclude with an example from neutron scattering, using data from a filter difference spectrometer to contrast MaxEnt with a conventional deconvolution. 12 refs., 8 figs., 1 tab

  3. Solar maximum observatory

    International Nuclear Information System (INIS)

    Rust, D.M.

    1984-01-01

    The successful retrieval and repair of the Solar Maximum Mission (SMM) satellite by Shuttle astronauts in April 1984 permitted continuance of solar flare observations that began in 1980. The SMM carries a soft X ray polychromator, gamma ray, UV and hard X ray imaging spectrometers, a coronagraph/polarimeter and particle counters. The data gathered thus far indicated that electrical potentials of 25 MeV develop in flares within 2 sec of onset. X ray data show that flares are composed of compressed magnetic loops that have come too close together. Other data have been taken on mass ejection, impacts of electron beams and conduction fronts with the chromosphere and changes in the solar radiant flux due to sunspots. 13 references

  4. Introduction to maximum entropy

    International Nuclear Information System (INIS)

    Sivia, D.S.

    1989-01-01

    The maximum entropy (MaxEnt) principle has been successfully used in image reconstruction in a wide variety of fields. The author reviews the need for such methods in data analysis and shows, by use of a very simple example, why MaxEnt is to be preferred over other regularizing functions. This leads to a more general interpretation of the MaxEnt method, and its use is illustrated with several different examples. Practical difficulties with non-linear problems still remain, this being highlighted by the notorious phase problem in crystallography. He concludes with an example from neutron scattering, using data from a filter difference spectrometer to contrast MaxEnt with a conventional deconvolution. 12 refs., 8 figs., 1 tab

  5. Functional Maximum Autocorrelation Factors

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Nielsen, Allan Aasbjerg

    2005-01-01

    MAF outperforms the functional PCA in concentrating the interesting' spectra/shape variation in one end of the eigenvalue spectrum and allows for easier interpretation of effects. Conclusions. Functional MAF analysis is a useful methods for extracting low dimensional models of temporally or spatially......Purpose. We aim at data where samples of an underlying function are observed in a spatial or temporal layout. Examples of underlying functions are reflectance spectra and biological shapes. We apply functional models based on smoothing splines and generalize the functional PCA in......\\verb+~+\\$\\backslash\\$cite{ramsay97} to functional maximum autocorrelation factors (MAF)\\verb+~+\\$\\backslash\\$cite{switzer85,larsen2001d}. We apply the method to biological shapes as well as reflectance spectra. {\\$\\backslash\\$bf Methods}. MAF seeks linear combination of the original variables that maximize autocorrelation between...

  6. Regularized maximum correntropy machine

    KAUST Repository

    Wang, Jim Jing-Yan; Wang, Yunji; Jing, Bing-Yi; Gao, Xin

    2015-01-01

    In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.

  7. Regularized maximum correntropy machine

    KAUST Repository

    Wang, Jim Jing-Yan

    2015-02-12

    In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.

  8. Usability Studies and User-Centered Design in Digital Libraries

    Science.gov (United States)

    Comeaux, David J.

    2008-01-01

    Digital libraries continue to flourish. At the same time, the principles of user-centered design and the practice of usability testing have been growing in popularity, spreading their influence into the library sphere. This article explores the confluence of these two trends by surveying the current literature on usability studies of digital…

  9. Users Views about the Usability of Digital Libraries

    Science.gov (United States)

    Koohang, Alex; Ondracek, James

    2005-01-01

    This study examined users' views about the usability of digital libraries' current and perceived importance. Age, gender, prior experience with the Internet, college status, and digital library proficiency are the independent variables. Users' current views about the usability of digital libraries and users perceived importance of digital library…

  10. Pilot implementation Driven by Effects Specifications and Formative Usability Evaluation

    DEFF Research Database (Denmark)

    Barlach, Anders; Hertzum, Morten; Simonsen, Jesper

    2013-01-01

    This chapter reports on the usability-engineering work performed throughout the pilot implementation of an Electronic Healthcare Record (EHR). The case describes and analyzes the use of pilot implementations to formatively evaluate whether the usability of the EHR meets the effects specified for ...

  11. IT investment decision making : Usability of a normative model

    NARCIS (Netherlands)

    Wijnhoven, Alphonsus B.J.M.; Heerkens, Johannes M.G.

    This article analyzes the usability of a multi-criteria decision analysis based on a real options AHP (ROAHP) method for IT-investment decisions. The study presents ROAHP to Chief Information Officers (CIO’s) and collects their opinions on prerequisites for usability, strengths and weaknesses. To

  12. Earning the Stamp of Approval: How To Achieve Optimal Usability.

    Science.gov (United States)

    Makar, Susan

    2003-01-01

    Describes the redesign of the Web site at the virtual library of the NIST (National Institute of Standards and Technology). Discusses usability problems with the original site, including navigation difficulties; focus groups to determine user needs; usability testing for the new Web site; and the importance of customer input. (LRW)

  13. New Options for Usability Testing Projects in Business Communication Courses

    Science.gov (United States)

    Jameson, Daphne A.

    2013-01-01

    The increasing availability of recording technologies makes it easier to include usability testing projects in business communication courses. Usability testing is a method of discovering whether people can navigate, read, and understand a print or electronic communication well enough to achieve a particular purpose in a reasonable time frame.…

  14. Post-deployment usability evaluation of a radiology workstation

    NARCIS (Netherlands)

    Jorritsma, Wiard; Cnossen, Fokie; Dierckx, Rudi; Oudkerk, Matthijs; van Ooijen, Peter

    2015-01-01

    Objective To evaluate the usability of a radiology workstation after deployment in a hospital. Significance In radiology, it is difficult to perform valid pre-deployment usability evaluations due to the heterogeneity of the user group, the complexity of the radiological workflow, and the complexity

  15. The Usability Expert’s Fear of Agility

    DEFF Research Database (Denmark)

    Nielsen, Lene; Madsen, Sabine

    2012-01-01

    This paper contributes to the HCI literature on usability practice with insights about the empirical challenges and global emerging practices caused by the advent of agile software development (ASD). In the paper we report from a worldwide study involving 12 usability professionals from 12 differ...

  16. Information users and usability in the digital age

    CERN Document Server

    Chowdhury, G G

    2013-01-01

    Gives an overview of the necessary issues relating to information users and the usability of information services in the digital world, including user-centred design, and the characteristics and behaviour of information users. This book helps readers understand why information users and the usability of information services are important.

  17. Training Software Developers and Designers to Conduct Usability Evaluations

    Science.gov (United States)

    Skov, Mikael Brasholt; Stage, Jan

    2012-01-01

    Many efforts to improve the interplay between usability evaluation and software development rely either on better methods for conducting usability evaluations or on better formats for presenting evaluation results in ways that are useful for software designers and developers. Both of these approaches depend on a complete division of work between…

  18. Revealing unawareness in usability related decision-making

    NARCIS (Netherlands)

    Harkema, C.L.E.

    2012-01-01

    Nowadays, many users experience usability issues with their electronic products. It does not work as they expect or otherwise irritates the user, so he becomes dissatisfied about the product and may even complain about it. Th ese numbers of complaints to companies and usability issues are high and

  19. Usability Plans and Schemes for Low Fidelity Prototypes

    DEFF Research Database (Denmark)

    Schultz, Nette; Kirk Sørensen, Jannick; Sørensen, Lene

    2006-01-01

    Internal report of WP1 task 4 activities from August 2006 to December 2006. This report describes the setup of a usability evaluation framework for evaluating core MAGNET concepts in terms of usability. Initially, these core concepts are identified and modes of operation involving...

  20. Reusable Software Usability Specifications for mHealth Applications.

    Science.gov (United States)

    Cruz Zapata, Belén; Fernández-Alemán, José Luis; Toval, Ambrosio; Idri, Ali

    2018-01-25

    One of the key factors for the adoption of mobile technologies, and in particular of mobile health applications, is usability. A usable application will be easier to use and understand by users, and will improve user's interaction with it. This paper proposes a software requirements catalog for usable mobile health applications, which can be used for the development of new applications, or the evaluation of existing ones. The catalog is based on the main identified sources in literature on usability and mobile health applications. Our catalog was organized according to the ISO/IEC/IEEE 29148:2011 standard and follows the SIREN methodology to create reusable catalogs. The applicability of the catalog was verified by the creation of an audit method, which was used to perform the evaluation of a real app, S Health, application created by Samsung Electronics Co. The usability requirements catalog, along with the audit method, identified several usability flaws on the evaluated app, which scored 83%. Some flaws were detected in the app related to the navigation pattern. Some more issues related to the startup experience, empty screens or writing style were also found. The way a user navigates through an application improves or deteriorates user's experience with the application. We proposed a reusable usability catalog and an audit method. This proposal was used to evaluate a mobile health application. An audit report was created with the usability issues identified on the evaluated application.

  1. A Usability Evaluation of Academic Virtual Reference Services

    Science.gov (United States)

    Chow, Anthony S.; Croxton, Rebecca A.

    2014-01-01

    This study examined the usability of five virtual reference services--instant messenger chat, e-mail, telephone, text messaging, and Skype videoconferencing--by having 31 undergraduate and graduate students evaluate the usability of the virtual reference services of two different universities. The study's results suggest that user preference and…

  2. Post-deployment usability evaluation of a radiology workstation

    NARCIS (Netherlands)

    Jorritsma, Wiard; Cnossen, Fokie; Dierckx, Rudi A.; Oudkerk, Matthijs; Van Ooijen, Peter M. A.

    Objectives: To determine the number, nature and severity of usability issues radiologists encounter while using a commercially available radiology workstation in clinical practice, and to assess how well the results of a pre-deployment usability evaluation of this workstation generalize to clinical

  3. How to Reach Evidence-Based Usability Evaluation Methods

    NARCIS (Netherlands)

    Marcilly, Romaric; Peute, Linda

    2017-01-01

    This paper discusses how and why to build evidence-based knowledge on usability evaluation methods. At each step of building evidence, requisites and difficulties to achieve it are highlighted. Specifically, the paper presents how usability evaluation studies should be designed to allow capitalizing

  4. Discovering the User: A Practical Glance at Usability Testing.

    Science.gov (United States)

    Campbell, Nicole; Walbridge, Sharon; Chisman, Janet; Diller, Karen R.

    1999-01-01

    This interview focuses on usability testing, one method for evaluating whether library Web sites are useful for users. Discussion includes: benefits and drawbacks of usability testing; why it is important; lessons learned from testing; advice for someone interested in doing a study; and recommendations. (AEF)

  5. Comparative study of heuristic evaluation and usability testing methods.

    Science.gov (United States)

    Thyvalikakath, Thankam Paul; Monaco, Valerie; Thambuganipalle, Himabindu; Schleyer, Titus

    2009-01-01

    Usability methods, such as heuristic evaluation, cognitive walk-throughs and user testing, are increasingly used to evaluate and improve the design of clinical software applications. There is still some uncertainty, however, as to how those methods can be used to support the development process and evaluation in the most meaningful manner. In this study, we compared the results of a heuristic evaluation with those of formal user tests in order to determine which usability problems were detected by both methods. We conducted heuristic evaluation and usability testing on four major commercial dental computer-based patient records (CPRs), which together cover 80% of the market for chairside computer systems among general dentists. Both methods yielded strong evidence that the dental CPRs have significant usability problems. An average of 50% of empirically-determined usability problems were identified by the preceding heuristic evaluation. Some statements of heuristic violations were specific enough to precisely identify the actual usability problem that study participants encountered. Other violations were less specific, but still manifested themselves in usability problems and poor task outcomes. In this study, heuristic evaluation identified a significant portion of problems found during usability testing. While we make no assumptions about the generalizability of the results to other domains and software systems, heuristic evaluation may, under certain circumstances, be a useful tool to determine design problems early in the development cycle.

  6. Usability evaluation of a locomotor therapy device considering different strategies

    Directory of Open Access Journals (Sweden)

    Langthaler Sonja

    2016-09-01

    Full Text Available Usability of medical devices is one of the main determining factors in preventing use errors in treatment and strongly correlates to patient safety and quality of treatment. This thesis demonstrates the usability testing and evaluation of a prototype for locomotor therapy of infants. Therefore, based on the normative requirements of the EN 62366, a concept combined of evaluation procedures and assessing methods was created to enable extensive testing and analysis of the different aspects of usability. On the basis of gathered information weak points were identified and appropriate measures were presented to increase the usability and operating safety of the locomotor prototype. The overall outcome showed an usability value of 77.4% and an evaluation score of 6.99, which can be interpreted as “satisfactory”.

  7. Usability engineering: domain analysis activities for augmented-reality systems

    Science.gov (United States)

    Gabbard, Joseph; Swan, J. E., II; Hix, Deborah; Lanzagorta, Marco O.; Livingston, Mark; Brown, Dennis B.; Julier, Simon J.

    2002-05-01

    This paper discusses our usability engineering process for the Battlefield Augmented Reality System (BARS). Usability engineering is a structured, iterative, stepwise development process. Like the related disciplines of software and systems engineering, usability engineering is a combination of management principals and techniques, formal and semi- formal evaluation techniques, and computerized tools. BARS is an outdoor augmented reality system that displays heads- up battlefield intelligence information to a dismounted warrior. The paper discusses our general usability engineering process. We originally developed the process in the context of virtual reality applications, but in this work we are adapting the procedures to an augmented reality system. The focus of this paper is our work on domain analysis, the first activity of the usability engineering process. We describe our plans for and our progress to date on our domain analysis for BARS. We give results in terms of a specific urban battlefield use case we have designed.

  8. Solar maximum mission

    International Nuclear Information System (INIS)

    Ryan, J.

    1981-01-01

    By understanding the sun, astrophysicists hope to expand this knowledge to understanding other stars. To study the sun, NASA launched a satellite on February 14, 1980. The project is named the Solar Maximum Mission (SMM). The satellite conducted detailed observations of the sun in collaboration with other satellites and ground-based optical and radio observations until its failure 10 months into the mission. The main objective of the SMM was to investigate one aspect of solar activity: solar flares. A brief description of the flare mechanism is given. The SMM satellite was valuable in providing information on where and how a solar flare occurs. A sequence of photographs of a solar flare taken from SMM satellite shows how a solar flare develops in a particular layer of the solar atmosphere. Two flares especially suitable for detailed observations by a joint effort occurred on April 30 and May 21 of 1980. These flares and observations of the flares are discussed. Also discussed are significant discoveries made by individual experiments

  9. A proposal for a repertory-grid study of differences in Chinese, Danish, and Indian conceptions of usability: Cultural usability?

    DEFF Research Database (Denmark)

    Hertzum, Morten

    2006-01-01

    This is an unrefined proposal for a study that could form part of the exploratory phase of the Cultural Usability project. The proposed study compares three cultures (Chinese, Danish, and Indian) and two stakeholder groups (users and developers) with respect to their conceptions of usability....

  10. Combining usability evaluations to highlight the chain that leads from usability flaws to usage problems and then negative outcomes.

    Science.gov (United States)

    Watbled, Ludivine; Marcilly, Romaric; Guerlinger, Sandra; Bastien, J-M Christian; Beuscart-Zéphir, Marie-Catherine; Beuscart, Régis

    2018-02-01

    Poor usability of health technology is thought to diminish work system performance, increase error rates and, potentially, harm patients. The present study (i) used a combination of usability evaluation methods to highlight the chain that leads from usability flaws to usage problems experienced by users and, ultimately, to negative patient outcomes, and (ii) validated this approach by studying two different discharge summary production systems. To comply with quality guidelines, the process of drafting and sending discharge summaries is increasingly being automated. However, the usability of these systems may modify their impact (or the absence thereof) in terms of production times and quality, and must therefore be evaluated. Here, we applied three successive techniques for usability evaluation (heuristic evaluation, user testing and field observation) to two discharge summary production systems (underpinned by different technologies). The systems' main usability flaws led respectively to an increase in the time need to produce a discharge summary and the risk of patient misidentification. Our results are discussed with regard to the possibility of linking the usability flaws, usage problems and the negative outcomes by successively applying three methods for evaluating usability (heuristic evaluation, user testing and in situ observations) throughout the system development life cycle. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Usability Testing Analysis on The Bana Game as Education Game Design References on Junior High School

    Directory of Open Access Journals (Sweden)

    F. Adnan

    2017-04-01

    Full Text Available Learning media is one of the important elements in the learning process. Technological development support makes learning media more varied. The approach of using digital technology as a learning media has a better and more effective impact than other approaches. In order to increase the students’ learning interest, it requires the support of an interesting learning media. The use of gaming applications as learning media can improve learning outcomes. The benefits of using the maximum application cannot be separated from the determination of application design. The Bana game aims to increase the ability of critical thinking of the junior high school students. The usability-testing analysis on the Bana game application is used in order to get the design reference as an educational game development. The game is used as an object of the analysis because it has the same characteristics and goals with the game application to be developed. Usability Testing is a method used to measure the ease of use of an application by users. The Usability Testing consists of learnability, efficiency, memorability, errors, and satisfaction. The results of the analysis obtained will be used as a reference for educational game applications that will be developed.

  12. Enhancing usability using Near Field Communication for mobile application

    Directory of Open Access Journals (Sweden)

    Wihidayat Endar

    2018-01-01

    Full Text Available Near Field Communication (NFC as relatively new wireless communication technology pushes new challenges to application developers to make their applications easier to use and simpler to operate. This point of view known as usability element. Usability is one of the elements for creating good quality applications. This study aims to analyse the usability of mobile-based application embeds with NFC. We also try to evaluate usability in applications used by children. We developed an application called Receptionist which has a primary function as a communication tool between students, teachers and parents at a middle school. To know the impact of the NFC, the Receptionist input system is designed with two methods, via conventional navigation (using buttons and via NFC. To understand the usability of each method, we do user testing and questioners on students. The results show, using the NFC there is a significant increase in usability attributes: efficiency, effectiveness, and learnability. On the other hand, there is decreases of user satisfaction comparing to conventional method. In general, this study demonstrates the potential of new input device technologies that can improve the usability of mobile-based applications.

  13. On the Concepts of Usability and Reusability of Learning Objects

    Directory of Open Access Journals (Sweden)

    Miguel-Angel Sicilia

    2003-10-01

    Full Text Available “Reusable learning objects” oriented towards increasing their potential reusability are required to satisfy concerns about their granularity and their independence of concrete contexts of use. Such requirements also entail that the definition of learning object “usability,” and the techniques required to carry out their “usability evaluation” must be substantially different from those commonly used to characterize and evaluate the usability of conventional educational applications. In this article, a specific characterization of the concept of learning object usability is discussed, which places emphasis on “reusability,” the key property of learning objects residing in repositories. The concept of learning object reusability is described as the possibility and adequacy for the object to be usable in prospective educational settings, so that usability and reusability are considered two interrelated – and in many cases conflicting – properties of learning objects. Following the proposed characterization of two characteristics or properties of learning objects, a method to evaluate usability of specific learning objects will be presented.

  14. Assessing the usability of Shazam mobile app

    Science.gov (United States)

    Hussain, Azham; Mkpojiogu, Emmanuel O. C.; Almazini, Hassan; Almazini, Hussein

    2017-10-01

    Like searching for a "needle" in a "haystack", suppose that there is a large set of signals (finite sequences of numbers) fs1; s2; s3; g, and a special signal q that may or may not be in the collection. How can the signals be found in the collection that is similar, or identical to q, and how can this be done quickly? A solution to this question is the basis of the Shazam smart phone app, where a listener captures a short excerpt of a recorded song with the smart phone's microphone, and in a matter of moments the app reports the name of the song and the artist. Here, the "needle" is the excerpt, and the "haystack" is a vast corpus of popular music. The Shazam algorithm is powered by Fourier analysis. This paper presents a report on a usability evaluation of Amazon Shazam app. The researchers present the outcome based on a task-based evaluation that involved 15 users of different level of experience who performed 5 tasks using the Shazam mobile app. Post-test questionnaire was used to capture users' perceptions about the app. The results demonstrate that most of the participants were satisfied with services provided by the app.

  15. Training Software Developers in Usability Engineering: A Literature Review

    DEFF Research Database (Denmark)

    Bruun, Anders

    2010-01-01

    . This paper presents a comprehensive literature study of research conducted in this area, where 129 papers are analyzed in terms of research focus, empirical basis, types of training participants and training costs. Findings show a need for further empirical research regarding long term effects of training...... to fund usability specialists or comprehensive consultancy. Training of non-usability personnel in critical usability engineering methods has the potential of easing these challenges. It is, however, unknown how much and what kind of research that has been committed to novice training in UE methods......, training costs and training in user based evaluation methods....

  16. Feedback from Usability Evaluation to User Interface Design

    DEFF Research Database (Denmark)

    Nielsen, C. M.; Overgaard, M.; Pedersen, M. B.

    2005-01-01

    This paper reports from an exploratory study of means for providing feedback from a usability evaluation to the user interface designers. In this study, we conducted a usability evaluation of a mobile system that is used by craftsmen to register use of time and materials. The results...... and weaknesses of the system. The findings indicate that detailed descriptions of problems and log descriptions of the user's interaction with the system and of system interaction are useful for the designers when trying to understand the usability problems that the users have encountered....

  17. Workshop on cultural usability and human work interaction design

    DEFF Research Database (Denmark)

    Clemmensen, Torkil; Ørngreen, Rikke; Roese, Kerstin

    2008-01-01

    it into interaction design. The workshop will present current research into cultural usability and human work interaction design. Cultural usability is a comprehensive concept, which adheres to all kinds of contexts in which humans are involved (private family, work, public and private organizations, nature......, Workplace observation, Think-Aloud Usability Test, etc. These techniques often give - seemingly - similar results when applied in diverse cultural settings, but experience shows that we need a deep understanding of the cultural, social and organizational context to interpret the results, and to transform...

  18. Integrating discount usability in scrum development process in Ethiopia

    DEFF Research Database (Denmark)

    Teka, Degif; Dittrich, Y.; Kifle, Mesfin

    2017-01-01

    be adapted and integrated into the Scrum-agile development with especial emphasis on the Ethiopian context. The research aims at adapting software engineering and ICT development methods to the specific situation and integrating user-centered design (UCD) and lightweight usability methods into agile...... end users and developers. Culturally adapted user pair testing and heuristic evaluation supported usability testing and supported developers in getting early feedback. Integrated approach of discount usability with the Scrum process has been developed and evaluated first with the involved...

  19. Usability of Computerized Lung Auscultation-Sound Software (CLASS) for learning pulmonary auscultation.

    Science.gov (United States)

    Machado, Ana; Oliveira, Ana; Jácome, Cristina; Pereira, Marco; Moreira, José; Rodrigues, João; Aparício, José; Jesus, Luis M T; Marques, Alda

    2018-04-01

    The mastering of pulmonary auscultation requires complex acoustic skills. Computer-assisted learning tools (CALTs) have potential to enhance the learning of these skills; however, few have been developed for this purpose and do not integrate all the required features. Thus, this study aimed to assess the usability of a new CALT for learning pulmonary auscultation. Computerized Lung Auscultation-Sound Software (CLASS) usability was assessed by eight physiotherapy students using computer screen recordings, think-aloud reports, and facial expressions. Time spent in each task, frequency of messages and facial expressions, number of clicks and problems reported were counted. The timelines of the three methods used were matched/synchronized and analyzed. The tasks exercises and annotation of respiratory sounds were the ones requiring more clicks (median 132, interquartile range [23-157]; 93 [53-155]; 91 [65-104], respectively) and where most errors (19; 37; 15%, respectively) and problems (n = 7; 6; 3, respectively) were reported. Each participant reported a median of 6 problems, with a total of 14 different problems found, mainly related with CLASS functionalities (50%). Smile was the only facial expression presented in all tasks (n = 54). CLASS is the only CALT available that meets all the required features for learning pulmonary auscultation. The combination of the three usability methods identified advantages/disadvantages of CLASS and offered guidance for future developments, namely in annotations and exercises. This will allow the improvement of CLASS and enhance students' activities for learning pulmonary auscultation skills.

  20. Usability and Accessibility of Air Force Intranet Web Sites

    National Research Council Canada - National Science Library

    Bentley, Richard S

    2006-01-01

    .... This research effort seeks to establish an understanding of how well common practice usability design principles and government mandated accessibility guidelines are followed by Air Force intranet web sites...

  1. Can eye tracking boost usability evaluation of computer games?

    DEFF Research Database (Denmark)

    Johansen, Sune Alstrup; Noergaard, Mie; Soerensen, Janus Rau

    2008-01-01

    Good computer games need to be challenging while at the same time being easy to use. Accordingly, besides struggling with well known challenges for usability work, such as persuasiveness, the computer game industry also faces system-specific challenges, such as identifying methods that can provide...... data on players' attention during a game. This position paper discusses how eye tracking may address three core challenges faced by computer game producer IO Interactive in their on-going work to ensure games that are fun, usable, and challenging. These challenges are: (1) Persuading game designers...... about the relevance of usability results, (2) involving game designers in usability work, and (3) identifying methods that provide new data about user behaviour and experience....

  2. Direct Integration: Training Software Developers to Conduct Usability Evaluations

    DEFF Research Database (Denmark)

    Skov, Mikael B.; Stage, Jan

    2008-01-01

    is based on an empirical study where 36 teams with a total of 234 first-year university students on software development and design educations were trained in a simple approach for user-based website usability testing that was taught in a 40 hour course. This approach supported them in planning, conducting......Many improvements of the interplay between usability evaluation and software development rely either on better methods for conducting usability evaluations or on better formats for presenting evaluation results in ways that are useful for software designers and developers. Both approaches involve...... a complete division of work between developers and evaluators, which is an undesirable complexity for many software development projects. This paper takes a different approach by exploring to what extent software developers and designers can be trained to carry out their own usability evaluations. The paper...

  3. Agents and wearables : usability in the COMRIS system

    NARCIS (Netherlands)

    Haan, de G.; Terken, J.M.B.

    2001-01-01

    This paper discusses usability research concerning a wearable system for spoken advice: a field experiment to investigate key concepts, a laboratory experiment to investigate interaction design, and field trials to evaluate the system. Conclusions are drawn about designing wearable appliances.

  4. The reliability and usability of district health information software ...

    African Journals Online (AJOL)

    The reliability and usability of district health information software: case studies from Tanzania. ... The District Health Information System (DHIS) software from the Health Information System ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  5. Availability and Usability of BHO Encounter Data in MAX 2009

    Data.gov (United States)

    U.S. Department of Health & Human Services — Availability and Usability of Behavioral Health Organization Encounter Data in MAX 2009, published in Volume 4, Issue 2 of Medicare and Medicaid Research Review,...

  6. Meta-Analysis of Correlations Among Usability Measures

    DEFF Research Database (Denmark)

    Hornbæk, Kasper Anders Søren; Effie Lai Chong, Law

    2007-01-01

    are generally low: effectiveness measures (e.g., errors) and efficiency measures (e.g., time) has a correlation of .247 ± .059 (Pearson's product-moment correlation with 95% confidence interval), efficiency and satisfaction (e.g., preference) one of .196 ± .064, and effectiveness and satisfaction one of .164......Understanding the relation between usability measures seems crucial to deepen our conception of usability and to select the right measures for usability studies. We present a meta-analysis of correlations among usability measures calculated from the raw data of 73 studies. Correlations...... ± .062. Changes in task complexity do not influence these correlations, but use of more complex measures attenuates them. Standard questionnaires for measuring satisfaction appear more reliable than homegrown ones. Measures of users' perceptions of phenomena are generally not correlated with objective...

  7. Social Context in Usability Evaluations: Concepts, Processes and Products

    DEFF Research Database (Denmark)

    Jensen, Janne Jul

    social context is considered important, only little research has been done to identify how it influences usability evaluations. In this thesis I explore how social context affects the process and product of a usability evaluation and explain the findings in terms of the theory of behaviour settings...... leader) and non-operatives (members, spectators, neutrals and potentials) from the theory of behaviour settings to usability evaluations generates an understanding and create an awareness of the level of power possessed by each of the participants in the social context. 2. On the operative level...... and a field experiment. Findings from these activities are presented in five published paper contributions. I furthermore introduce the theory of behaviour settings as a tool to help characterise the key concepts of social context which, together with an understanding of usability evaluations, provide...

  8. Usability Analysis of the Channel Application Programming Interface

    National Research Council Canada - National Science Library

    Brown, Christopher

    2003-01-01

    ... has ever used the API; hence, no analysis was accomplished with respect to usability attributes, The project sponsor desires public release of the API, especially within the Department of Defense (DoD...

  9. A Novel Multifactor Authentication System Ensuring Usability and Security

    OpenAIRE

    Mathew, Gloriya; Thomas, Shiney

    2013-01-01

    User authentication is one of the most important part of information security. Computer security most commonly depends on passwords to authenticate human users. Password authentication systems will be either been usable but not secure, or secure but not usable. While there are different types of authentication systems available alphanumeric password is the most commonly used authentication mechanism. But this method has significant drawbacks. An alternative solution to the text based authenti...

  10. Development of a Customizable Health IT Usability Evaluation Scale

    Science.gov (United States)

    Yen, Po-Yin; Wantland, Dean; Bakken, Suzanne

    2010-01-01

    We developed a customizable questionnaire, the Health Information Technology (IT) Usability Evaluation Scale (Health-ITUES) and conducted an exploratory factor analysis to examine the scale’s psychometric properties. Nurses (n=377) completed Health-ITUES to rate the usability of a web-based communication system for scheduling nursing staff. The analysis revealed a four-factor structure of Health-ITUES. The results provided preliminary evidence for the factorial validity and internal consistency reliability of Health-ITUES. PMID:21347112

  11. Online user tracking and usability tools - a mapping study

    OpenAIRE

    Nyström, Niklas

    2014-01-01

    Tracking user activities online can be done in order to improve systems usability, understand user behaviour or to increase monetary prot, to mention a few things. The software tools for this purpose can vary, for example in terms of usability of the tool itself, features, security, price, accessibility and support options. In this study I have developed a methodology to evaluate a selection of modern tools and map them depending on various properties. I have also analysed learning theories t...

  12. Why Citizen Science Without Usability Testing Will Underperform

    Science.gov (United States)

    Romano, C.; Gay, P.; Owens, R.; Burlea, G.

    2017-12-01

    Citizen science projects must undergo usability testing and optimization if they are to meet their stated goals. This presentation will include video of usability tests conducted upon citizen science websites. Usability testing is essential to the success of online interaction, however, citizen science projects have just begun to include this critical activity. Interaction standards in citizen science lag behind those of commercial interests, and published research on this topic is limited. Since online citizen science is by definition, an exchange of information, a clear understanding of how users experience an online project is essential to informed decision-making. Usability testing provides that insight. Usability testing collects data via direct observation of a person while she interacts with a digital product, such as a citizen science website. The test participant verbalizes her thoughts while using the website or application; the moderator follows the participant and captures quantitative measurement of the participant's confidence of success as she advances through the citizen science project. Over 15 years of usability testing, we have observed that users who do not report a consistent sense of progress are likely to abandon a website after as few as three unrewarding interactions. Since citizen science is also a voluntary activity, ensuring seamless interaction for users is mandatory. Usability studies conducted on citizen science websites demonstrate that project teams frequently underestimate a user's need for context and ease of use. Without usability testing, risks to online citizen science projects include high bounce rate (users leave the website without taking any action), abandonment (of the website, tutorials, registration), misunderstanding instructions (causing disorientation and erroneous conclusions), and ultimately, underperforming projects.

  13. Evaluating Usability of E-Learning Systems in Universities

    OpenAIRE

    Nicholas Kipkurui Kiget; Professor G. Wanyembi; Anselemo Ikoha Peters

    2014-01-01

    The use of e-learning systems has increased significantly in the recent times. E-learning systems are supplementing teaching and learning in universities globally. Kenyan universities have adopted e-learning technologies as means for delivering course content. However despite adoption of these systems, there are considerable challenges facing the usability of the systems. Lecturers and students have different perceptions in regard to the usability of e-learning systems. The aim of this study ...

  14. Web usability testing with a Hispanic medically underserved population.

    Science.gov (United States)

    Moore, Mary; Bias, Randolph G; Prentice, Katherine; Fletcher, Robin; Vaughn, Terry

    2009-04-01

    Skilled website developers value usability testing to assure user needs are met. When the target audience differs substantially from the developers, it becomes essential to tailor both design and evaluation methods. In this study, researchers carried out a multifaceted usability evaluation of a website (Healthy Texas) designed for Hispanic audiences with lower computer literacy and lower health literacy. METHODS INCLUDED: (1) heuristic evaluation by a usability engineer, (2) remote end-user testing using WebEx software; and (3) face-to-face testing in a community center where use of the website was likely. Researchers found standard usability testing methods needed to be modified to provide interpreters, increased flexibility for time on task, presence of a trusted intermediary such as a librarian, and accommodation for family members who accompanied participants. Participants offered recommendations for website redesign, including simplified language, engaging and relevant graphics, culturally relevant examples, and clear navigation. User-centered design is especially important when website developers are not representative of the target audience. Failure to conduct appropriate usability testing with a representative audience can substantially reduce use and value of the website. This thorough course of usability testing identified improvements that benefit all users but become crucial when trying to reach an underserved audience.

  15. Evaluation Methods on Usability of M-Learning Environments

    Directory of Open Access Journals (Sweden)

    Teresa Magal-Royo

    2007-10-01

    Full Text Available Nowadays there are different evaluation methods focused in the assessment of the usability of telematic methods. The assessment of 3rd generation web environments evaluates the effectiveness and usability of application with regard to the user needs. Wireless usability and, specifically in mobile phones, is concentrated in the validation of the features and tools management using conventional interactive environments. There is not a specific and suitable criterion to evaluate created environments and m-learning platforms, where the restricted and sequential representation is a fundamental aspect to be considered.The present paper exposes the importance of the conventional usability methods to verify both: the employed contents in wireless formats, and the possible interfaces from the conception phases, to the validations of the platform with such characteristics.The development of usability adapted inspection could be complemented with the Remote’s techniques of usability testing, which are being carried out these days in the mobile devices field and which pointed out the need to apply common criteria in the validation of non-located learning scenarios.

  16. Health Information Technology Usability Evaluation Scale (Health-ITUES) for Usability Assessment of Mobile Health Technology: Validation Study.

    Science.gov (United States)

    Schnall, Rebecca; Cho, Hwayoung; Liu, Jianfang

    2018-01-05

    Mobile technology has become a ubiquitous technology and can be particularly useful in the delivery of health interventions. This technology can allow us to deliver interventions to scale, cover broad geographic areas, and deliver technologies in highly tailored ways based on the preferences or characteristics of users. The broad use of mobile technologies supports the need for usability assessments of these tools. Although there have been a number of usability assessment instruments developed, none have been validated for use with mobile technologies. The goal of this work was to validate the Health Information Technology Usability Evaluation Scale (Health-ITUES), a customizable usability assessment instrument in a sample of community-dwelling adults who were testing the use of a new mobile health (mHealth) technology. A sample of 92 community-dwelling adults living with HIV used a new mobile app for symptom self-management and completed the Health-ITUES to assess the usability of the app. They also completed the Post-Study System Usability Questionnaire (PSSUQ), a widely used and well-validated usability assessment tool. Correlations between these scales and each of the subscales were assessed. The subscales of the Health-ITUES showed high internal consistency reliability (Cronbach alpha=.85-.92). Each of the Health-ITUES subscales and the overall scale was moderately to strongly correlated with the PSSUQ scales (r=.46-.70), demonstrating the criterion validity of the Health-ITUES. The Health-ITUES has demonstrated reliability and validity for use in assessing the usability of mHealth technologies in community-dwelling adults living with a chronic illness. ©Rebecca Schnall, Hwayoung Cho, Jianfang Liu. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 05.01.2018.

  17. Usability Assessment of International Office Website of Diponegoro University With Scenario Based Usability Evaluation Method and Wammi Method

    OpenAIRE

    Ratna Purwaningsih; Ikhsan Yenifi

    2015-01-01

    Website development needs to pay attention to usability aspect which consist of four factors: efficiency, effectiveness, satisfactions and error rate. The website of International Office of Diponegoro University provides academic information for Indonesian students and foreign students. The website still has some problem, especially on searching certain information. This research aims to evaluate the design of the existing website and measures the usability. A well-designed website will help ...

  18. Making Scientific Data Usable and Useful

    Science.gov (United States)

    Satwicz, T.; Bharadwaj, A.; Evans, J.; Dirks, J.; Clark Cole, K.

    2017-12-01

    Transforming geological data into information that has broad scientific and societal impact is a process fraught with barriers. Data sets and tools are often reported to have poor user experiences (UX) that make scientific work more challenging than it needs be. While many other technical fields have benefited from ongoing improvements to the UX of their tools (e.g., healthcare and financial services) scientists are faced with using tools that are labor intensive and not intuitive. Our research team has been involved in a multi-year effort to understand and improve the UX of scientific tools and data sets. We use a User-Centered Design (UCD) process that involves naturalistic behavioral observation and other qualitative research methods adopted from Human-Computer Interaction (HCI) and related fields. Behavioral observation involves having users complete common tasks on data sets, tools, and websites to identify usability issues and understand the severity of the issues. We measure how successfully they complete tasks and diagnosis the cause of any failures. Behavioral observation is paired with in-depth interviews where users describe their process for generating results (from initial inquiry to final results). By asking detailed questions we unpack common patterns and challenges scientists experience while working with data. We've found that tools built using the UCD process can have a large impact on scientist work flows and greatly reduce the time it takes to process data before analysis. It is often challenging to understand the organization and nuances of data across scientific fields. By better understanding how scientists work we can create tools that make routine tasks less-labor intensive, data easier to find, and solve common issues with discovering new data sets and engaging in interdisciplinary research. There is a tremendous opportunity for advancing scientific knowledge and helping the public benefit from that work by creating intuitive, interactive

  19. Narrow band interference cancelation in OFDM: Astructured maximum likelihood approach

    KAUST Repository

    Sohail, Muhammad Sadiq; Al-Naffouri, Tareq Y.; Al-Ghadhban, Samir N.

    2012-01-01

    This paper presents a maximum likelihood (ML) approach to mitigate the effect of narrow band interference (NBI) in a zero padded orthogonal frequency division multiplexing (ZP-OFDM) system. The NBI is assumed to be time variant and asynchronous

  20. Web usability evaluation on BloobIS website by using hallway usability testing method and ISO 9241:11

    Science.gov (United States)

    Dwi Susanto, Tony; Ingesti Prasetyo, Anisa; Astuti, Hanim Maria

    2018-03-01

    At this moment, the need for web as an information media is highly important. Not only confined in the infotainment area, government, and education, but health as well uses the web media as a medium for providing information effectively. BloobIS is a web based application which integrates blood supply and distribution information at the Blood Transfusion Unit. Knowing how easy information is on BloobIS is marked by how convenient the website is used. Up until now, the BloobIS website is nearing completion but testing has not yet been performed to users and is on the testing and development phase in the Development Life Cycle software. Thus, an evaluation namely the quality control software which focuses on the perspective of BloobIs web usability is required. Hallway Usability Testing and ISO 9241:11 are the methods chosen to measure the BloobIS application usability. The expected outputs of the quality control software focusing on the usability evaluation are being able to rectify the usability deficiencies on the BloobIs web and provide recommendations to develop the web as a basic BloobIS web quality upgraed which sets a goal to amplify the satisfaction of web users based on usability factors in ISO 9241:11.

  1. Usability Test of an Interactive Dietary Recording

    Science.gov (United States)

    Chung, Louisa Ming Yan; Chung, Joanne Wai Yee; Wong, Thomas Kwok Shing

    2009-01-01

    Dietary intake methods are used to collect one's diet habit which is essential in nutrition assessment. Food diary, food frequency questionnaire (FFQ) and 24-hour recalls are the most common dietary intake methods. However, they are not welcomed by most clients. Digital handheld devices are now readily available, and the cost of digital…

  2. Usability evaluation of augmented reality user interfaces in games and personal navigation assistants

    OpenAIRE

    Ivanec, Zorian

    2017-01-01

    This paper studies heuristic usability evaluation of user interfaces. The literature review distinguishes characteristics of augmented reality and smartphones, presents heuristic evaluation, PACMAD usability model, personal navigation assistants, video games, augmented reality and J. Nielsen usability heuristics. In research part, usability heuristics of related subject fields and design guidelines are combined. Created heuristics and control questionnaire are used for evaluation of augmented...

  3. A Survey of Usability Practices in Free/Libre/Open Source Software

    Science.gov (United States)

    Paul, Celeste Lyn

    A review of case studies about usability in eight Free/Libre/Open Source Software (FLOSS) projects showed that an important issue regarding a usability initiative in the project was the lack of user research. User research is a key component in the user-centered design (UCD) process and a necessary step for creating usable products. Reasons why FLOSS projects suffered from a lack of user research included poor or unclear project leadership, cultural differences between developer and designers, and a lack of usability engineers. By identifying these critical issues, the FLOSS usability community can begin addressing problems in the efficacy of usability activities and work towards creating more usable FLOSS products.

  4. Credal Networks under Maximum Entropy

    OpenAIRE

    Lukasiewicz, Thomas

    2013-01-01

    We apply the principle of maximum entropy to select a unique joint probability distribution from the set of all joint probability distributions specified by a credal network. In detail, we start by showing that the unique joint distribution of a Bayesian tree coincides with the maximum entropy model of its conditional distributions. This result, however, does not hold anymore for general Bayesian networks. We thus present a new kind of maximum entropy models, which are computed sequentially. ...

  5. Usability evaluation with mental health professionals and young people to develop an Internet-based cognitive-behaviour therapy program for adolescents with anxiety disorders.

    Science.gov (United States)

    Wozney, Lori; Baxter, Pamela; Newton, Amanda S

    2015-12-16

    Use of the Internet to deliver cognitive behavioural therapy, a frontline treatment for anxiety disorders, is emerging as an option to increase access to treatment among adolescents with anxiety disorders. This study examined the usability of the Internet-based component of Breathe, a CBT program designed for adolescents with mild to moderate anxiety and impairments. A mixed-method usability testing design with semi-structured interviews, task completion, and survey by trained usability moderators was undertaken with two interactive cycles to determine the usability (ease of use, efficiency, errors, and user satisfaction) of the user interface and content areas of the program. Purposeful sampling was used to recruit mental health clinicians with expertise in treating adolescent anxiety disorders and young people aged 15 to 24 years involved. Testing involved using Web-conferencing software that allowed remote participation through personal computers. Two testing cycles involved participants completing structured 'think aloud' and 'cognitive walkthrough' tasks within the program. At the end of each cycle participants completed a 15-item global usability evaluation survey and were asked a series of open-ended questions. Descriptive and simple content analyses were used to identify and score usability issues for frequency and severity. Five clinicians and four young people (all user performance indicators (i.e., learnability, efficiency and number of errors) and user satisfaction. Participants were able to complete all critical tasks with minimal errors. Errors and issues identified during testing were predominantly around enhancements to the visual design and navigational support. Opinions across usability elements did not differ between young people and clinician participants. A multi-method remote usability approach provided the opportunity to improve the technical interface, therapeutic messaging and user experience of an Internet-based treatment program for

  6. Usability testing of a respiratory interface using computer screen and facial expressions videos.

    Science.gov (United States)

    Oliveira, Ana; Pinho, Cátia; Monteiro, Sandra; Marcos, Ana; Marques, Alda

    2013-12-01

    Computer screen videos (CSVs) and users' facial expressions videos (FEVs) are recommended to evaluate systems performance. However, software combining both methods is often non-accessible in clinical research fields. The Observer-XT software is commonly used for clinical research to assess human behaviours. Thus, this study reports on the combination of CSVs and FEVs, to evaluate a graphical user interface (GUI). Eight physiotherapists entered clinical information in the GUI while CSVs and FEVs were collected. The frequency and duration of a list of behaviours found in FEVs were analysed using the Observer-XT-10.5. Simultaneously, the frequency and duration of usability problems of CSVs were manually registered. CSVs and FEVs timelines were also matched to verify combinations. The analysis of FEVs revealed that the category most frequently observed in users behaviour was the eye contact with the screen (ECS, 32±9) whilst verbal communication achieved the highest duration (14.8±6.9min). Regarding the CSVs, 64 problems, related with the interface (73%) and the user (27%), were found. In total, 135 usability problems were identified by combining both methods. The majority were reported through verbal communication (45.8%) and ECS (40.8%). "False alarms" and "misses" did not cause quantifiable reactions and the facial expressions problems were mainly related with the lack of familiarity (55.4%) felt by users when interacting with the interface. These findings encourage the use of Observer-XT-10.5 to conduct small usability sessions, as it identifies emergent groups of problems by combining methods. However, to validate final versions of systems further validation should be conducted using specialized software. © 2013 Published by Elsevier Ltd.

  7. High and low spatial frequencies in website evaluations.

    Science.gov (United States)

    Thielsch, Meinald T; Hirschfeld, Gerrit

    2010-08-01

    Which features of websites are important for users' perceptions regarding aesthetics or usability? This study investigates how evaluations of aesthetic appeal and usability depend on high vs. low spatial frequencies. High spatial frequencies convey information on fine details, whereas low spatial frequencies convey information about the global layout. Participants rated aesthetic appeal and usability of 50 website screenshots from different domains. Screenshots were presented unfiltered, low-pass filtered with blurred targets or high-pass filtered with high-pass filtered targets. The main result is that low spatial frequencies can be seen to have a unique contribution in perceived website aesthetics, thus confirming a central prediction from processing fluency theory. There was no connection between low spatial frequencies and usability evaluations, whereas strong correlations were found between ratings of high-pass filtered websites and those of unfiltered websites in aesthetics and usability. This study thus offers a new perspective on the biological basis of users' website perceptions. This research links ergonomics to neurocognitive models of visual processing. This paper investigates how high and low spatial frequencies, which are neurologically processed in different visual pathways, independently contribute to users' perceptions of websites. This is very relevant for theories of website perceptions and for practitioners of web design.

  8. Usability inspection to improve an electronic provincial medication repository.

    Science.gov (United States)

    Kitson, Nicole A; Price, Morgan; Bowen, Michael; Lau, Francis

    2013-01-01

    Medication errors are a significant source of actual and potential harm for patients. Community medication records have the potential to reduce medication errors, but they can also introduce unintended consequences when there is low fit to task (low cognitive fit). PharmaNet is a provincially managed electronic repository that contains the records for community-based pharmacy-dispensed medications in British Columbia. This research explores the usability of PharmaNet, as a representative community-based medication repository. We completed usability inspections of PharmaNet through vendor applications. Vendor participants were asked to complete activity-driven scenarios, which highlighted aspects of medication management workflow. Screen recording was later reviewed. Heuristics were applied to explore usability issues and improvement opportunities. Usability inspection was conducted with four PharmaNet applications. Ninety-six usability issues were identified; half of these had potential implications for patient safety. These were primarily related to login and logout procedures; display of patient name; display of medications; update and display of alert information; and the changing or discontinuation of medications. PharmaNet was designed primarily to support medication dispensing and billing activities by community pharmacies, but is also used to support care providers with monitoring and prescribing activities. As such, some of the features do not have a strong fit for other clinical activities. To improve fit, we recommend: having a Current Medications List and Displaying Medication Utilization Charts.

  9. The Usability Analysis of An E-Learning Environment

    Directory of Open Access Journals (Sweden)

    Fulya TORUN

    2015-10-01

    Full Text Available In this research, an E-learning environment is developed for the teacher candidates taking the course on Scientific Research Methods. The course contents were adapted to one of the constructivist approach models referred to as 5E, and an expert opinion was received for the compliance of this model. An usability analysis was also performed to determine the usability of the e-learning environment. The participants of the research comprised 42 teacher candidates. The mixed method was used in the research. 3 different data collection tools were used in order to measure the three basic concepts of usability analyses, which are the dimensions of effectiveness, efficiency and satisfaction. Two of the data collection tools were the scales developed by different researchers and were applied with the approval received from the researchers involved. On the other hand, the usability test as another data tool was prepared by the researchers who conducted this study for the purpose of determining the participants’ success in handling the twelve tasks assigned to them with respect to the use of elearning environment, the seconds they spent on that environment and the number of clicks they performed. Considering the results of the analyses performed within the data obtained, the usability of the developed e-learning environment proved to be at a higher rate.

  10. Dimensions for hearing-impaired mobile application usability model

    Science.gov (United States)

    Nathan, Shelena Soosay; Hussain, Azham; Hashim, Nor Laily; Omar, Mohd Adan

    2017-10-01

    This paper discuss on the dimensions that has been derived for the hearing-impaired mobile applications usability model. General usability model consist of general dimension for evaluating mobile application however requirements for the hearing-impaired are overlooked and often scanted. This led towards mobile application developed for the hearing-impaired are left unused. It is also apparent that these usability models do not consider accessibility dimensions according to the requirement of the special users. This complicates the work of usability practitioners as well as academician that practices research usability when application are developed for the specific user needs. To overcome this issue, dimension chosen for the hearing-impaired are ensured to be align with the real need of the hearing-impaired mobile application. Besides literature studies, requirements for the hearing-impaired mobile application have been identified through interview conducted with hearing-impaired mobile application users that were recorded as video outputs and analyzed using Nvivo. Finally total of 6 out of 15 dimensions gathered are chosen for the proposed model and presented.

  11. Methods in Mapping Usability of Malaysia’s Shopping Centre

    Directory of Open Access Journals (Sweden)

    Abdul Ghani Aida Affina

    2016-01-01

    Full Text Available With more than 200 number of shopping centre in Klang Valley itself, we the consumer actually have vast of choices. Instead of the machineries varieties from the lower class product till the posh one, each of those shopping centres eventually offers the typical product same as others. Those shopping centers are competing with each other and in great endeavour to attract more consumers, to visit and spend. As for the visitor, the typical product and boring ambience seems similar in all malls, and is looking something beyond the standard. Something that promising quality embedded in shopping centre which evokes the various emotions of the user along their journey in malls. This quality is known as usability. Usability; as defined generally is a global user’s experience response with product, environment, service or facilities. It is an assessment in extracting the qualities of shopping centre design. In mapping it, there are a few synthesizing methods to implement it. Therefore, this paper purposely to review the method that been used in usability of Malaysia’s shopping centre research with a few references on previous research done in usability assessment by predecessor’s scholars. With the accentuation on three elements that anchoring what the usability is: effectiveness, efficient and satisfaction, it is hope that this overview can lead other researcher in portraying its relationship with the quality and ‘user friendly’ design of shopping centre.

  12. Usability challenges in an Ethiopian software development organization

    DEFF Research Database (Denmark)

    Teka, Degif; Dittrich, Yvonne; Kifle, Mesfin

    2016-01-01

    Usability and user centered design (UCD) are central to software development. In developing countries, the gap between IT development and the local use situation is larger than in western countries. However, usability is neither well addressed in software practice nor at the policy making level...... in Ethiopia. Software practitioners focus on functional requirements, meeting deadlines and budget. The software development industry in Ethiopia is in its early stage. The article aims at understanding usability practices in an Ethiopian software development company. Developers, system analysts, product...... configuration, their experience, cultural knowledge and common sense regarding the users' situation guided the design. Prototypes and fast delivery of working versions helped in getting user feedback even if early user focus proved to be a challenge as communication between developers and users suffered from...

  13. Usability Briefing - a process model for healthcare facilities

    DEFF Research Database (Denmark)

    Fronczek-Munter, Aneta

    2014-01-01

    Background: In complex buildings with many types of users it can be difficult to satisfy the numerous, often contradictory requirements. Research in usability mostly focuses on evaluating products or facilities with users, after they were built. This paper is part of a PhD project “Usability...... with various users/stakeholders, using creative boundary objects at workshops.  Practical Implications: The research results have relevance to researchers, client organisations, facility managers and architects planning new complex facilities.  Research limitations: The proposed model is theoretical and needs...... briefing for hospitals”, where methods for capturing user needs and experiences at hospital facilities are investigated in order to feed into design processes and satisfy the users’ needs and maximise the effectiveness of facilities. Purpose: This paper introduces the concept of usability briefing...

  14. Usability evaluation model for mobile e-book applications

    Science.gov (United States)

    Matraf, Munya Saleh Ba; Hussain, Azham

    2017-10-01

    Evaluation for mobile e-book applications are limited and did not address all the important usability measurements. Hence, this study aimed to identify the characteristics that affect user satisfaction on the usability of mobile e-book applications. Five characteristics that have a significant effect on the user satisfaction of mobile e-book applications have been identified namely readability, effectiveness, accessibility, efficiency, and navigation. A usability evaluation was conducted on three mobile e-book applications namely Adobe Acrobat Reader, Ebook Reader, and Amazon Kindle. 30 students from Universiti Utara Malaysia evaluated the mobile e-book applications and their satisfaction was measured using questionnaire. The outcomes discovered that the five characteristics have a significant positive relationship with user satisfaction. This provides insights into the main characteristics that increase user satisfaction.

  15. Accessibility and usability OCW data: The UTPL OCW

    Directory of Open Access Journals (Sweden)

    Germania Rodríguez

    2017-08-01

    Full Text Available This data article provides a data description on article entitled “A framework for improving web accessibility and usability of Open Course Ware sites” [3] This Data in Brief presents the data obtained from the accessibility and usability evaluation of the UTPL OCW. The data obtained from the framework evaluation consists of the manual evaluation of the standards criteria and the automatic evaluation of the tools Google PageSpeed and Google Analytics. In addition, this article presents the synthetized tables from standards that are used by the framework to evaluate the accessibility and usability of OCW, and the questionnaires required to extract the data. As a result, the article also provides the data required to reproduce the evaluation of other OCW.

  16. Usability principles to design mobile workplace learning content

    Directory of Open Access Journals (Sweden)

    Alessia Messuti

    2015-04-01

    Full Text Available The article describes the design of a mobile workplace learning tool for trainers of the International Training Centre of the International Labour Organization. The motivation behind is to provide trainers with a practical tool that will enable them to recall information at the moment of need and continue to learn in context. On this purpose a set of visual augmented reality cards was created, taking into consideration the fundamental mobile learning and usability principles. The nature of the article is empirical as it reports an experiment carried out with trainers which aimed at testing cards usability and learnability. Results show that the integration of both online and offline strategies was perceived as an added value as trainers could choose to retrieve information as they mostly like; finally, it also resulted in high usability scores, an aspect that contributes to their effectiveness at the workplace.

  17. Usability evaluation of mobile applications; where do we stand?

    Science.gov (United States)

    Zahra, Fatima; Hussain, Azham; Mohd, Haslina

    2017-10-01

    The range and availability of mobile applications is expanding rapidly. With the increased processing power available on portable devices, developers are increasing the range of services by embracing smartphones in their extensive and diverse practices. While usability testing and evaluations of mobile applications have not yet touched the accuracy level of other web based applications. The existing usability models do not adequately capture the complexities of interacting with applications on a mobile platform. Therefore, this study aims to presents review on existing usability models for mobile applications. These models are in their infancy but with time and more research they may eventually be adopted. Moreover, different categories of mobile apps (medical, entertainment, education) possess different functional and non-functional requirements thus customized models are required for diverse mobile applications.

  18. Software Usability: Concepts, Attributes and Associated Health Problems

    Directory of Open Access Journals (Sweden)

    Grīnberga Sabīne

    2016-10-01

    Full Text Available Digital technologies have opened a large set of opportunities for new electronic services (e-commerce, e-health, e-studies etc.. There are many considerations that need to be made when programmers are building new application software or system software. The software needs to be attractive enough that people want to look at it. It also needs to contain all necessary information that developers want to share with their readers (customers, users in order to help them achieve the objective for which they came to their website, use their software, or interact with their teaching packages. The oversupply of e-services products has created a need for usability research and development. “Usability means making products and systems easier to use, and matching them more closely to user needs and requirements”. Usability is a key concept of the human-computer interface and is concerned with making computer systems easy to learn and easy to use through a user-centered design process. The in-depth understanding of usability concepts and processes are critical for large-scale acceptance of new e-services and knowledge productivity. Poorly designed software can be extremely annoying to users. Smith and Mayes state that „usability is now recognised as a vital determining factor in the success of any new computer system or computer-based service”. Studies have shown that the main health problems of computer users are repetitive strain injuries, visual discomfort and stress-related disorders. Beside other risk factors, such as poor workstation design, uncomfortable work postures, long hours of computer use every day, stress, etc., also poor design and usability of the computer systems, as well as computer technical problems, add to the pressure felt by the user, which may in turn cause stress-related disorders.

  19. Usability/Sentiment for the Enterprise and ENTERPRISE

    Science.gov (United States)

    Meza, David; Berndt, Sarah

    2014-01-01

    The purpose of the Sentiment of Search Study for NASA Johnson Space Center (JSC) is to gain insight into the intranet search environment. With an initial usability survey, the authors were able to determine a usability score based on the Systems Usability Scale (SUS). Created in 1986, the freely available, well cited, SUS is commonly used to determine user perceptions of a system (in this case the intranet search environment). As with any improvement initiative, one must first examine and document the current reality of the situation. In this scenario, a method was needed to determine the usability of a search interface in addition to the user's perception on how well the search system was providing results. The use of the SUS provided a mechanism to quickly ascertain information in both areas, by adding one additional open-ended question at the end. The first ten questions allowed us to examine the usability of the system, while the last questions informed us on how the users rated the performance of the search results. The final analysis provides us with a better understanding of the current situation and areas to focus on for improvement. The power of search applications to enhance knowledge transfer is indisputable. The performance impact for any user unable to find needed information undermines project lifecycle, resource and scheduling requirements. Ever-increasing complexity of content and the user interface make usability considerations for the intranet, especially for search, a necessity instead of a 'nice-to-have'. Despite these arguments, intranet usability is largely disregarded due to lack of attention beyond the functionality of the infrastructure (White, 2013). The data collected from users of the JSC search system revealed their overall sentiment by means of the widely-known System Usability Scale. Results of the scores suggest 75%, +/-0.04, of the population rank the search system below average. In terms of a grading scaled, this equated to D or

  20. Website Usability in Asia “From Within”

    DEFF Research Database (Denmark)

    Nawaz, Ather; Clemmensen, Torkil

    2013-01-01

    As the number of website users in Asia grows, there is an increasing need to gain an overview of human–computer interaction (HCI) research about users and websites in that context. This article presents an overview of HCI research on website usability in Asia “from within,” which outlines...... discusses the results and the need for a greater sensitivity to what is “local” and “from within” in HCI research and what this can add to the existing literature on website usability....

  1. Multi-Channel Maximum Likelihood Pitch Estimation

    DEFF Research Database (Denmark)

    Christensen, Mads Græsbøll

    2012-01-01

    In this paper, a method for multi-channel pitch estimation is proposed. The method is a maximum likelihood estimator and is based on a parametric model where the signals in the various channels share the same fundamental frequency but can have different amplitudes, phases, and noise characteristics....... This essentially means that the model allows for different conditions in the various channels, like different signal-to-noise ratios, microphone characteristics and reverberation. Moreover, the method does not assume that a certain array structure is used but rather relies on a more general model and is hence...

  2. Maximum Temperature Detection System for Integrated Circuits

    Science.gov (United States)

    Frankiewicz, Maciej; Kos, Andrzej

    2015-03-01

    The paper describes structure and measurement results of the system detecting present maximum temperature on the surface of an integrated circuit. The system consists of the set of proportional to absolute temperature sensors, temperature processing path and a digital part designed in VHDL. Analogue parts of the circuit where designed with full-custom technique. The system is a part of temperature-controlled oscillator circuit - a power management system based on dynamic frequency scaling method. The oscillator cooperates with microprocessor dedicated for thermal experiments. The whole system is implemented in UMC CMOS 0.18 μm (1.8 V) technology.

  3. Towards a Usability and Error "Safety Net": A Multi-Phased Multi-Method Approach to Ensuring System Usability and Safety.

    Science.gov (United States)

    Kushniruk, Andre; Senathirajah, Yalini; Borycki, Elizabeth

    2017-01-01

    The usability and safety of health information systems have become major issues in the design and implementation of useful healthcare IT. In this paper we describe a multi-phased multi-method approach to integrating usability engineering methods into system testing to ensure both usability and safety of healthcare IT upon widespread deployment. The approach involves usability testing followed by clinical simulation (conducted in-situ) and "near-live" recording of user interactions with systems. At key stages in this process, usability problems are identified and rectified forming a usability and technology-induced error "safety net" that catches different types of usability and safety problems prior to releasing systems widely in healthcare settings.

  4. Usability and Acceptability of Balance Exergames in Older Adults

    DEFF Research Database (Denmark)

    Nawaz, Ather; Skjæret, Nina; Lægdheim Helbostad, Jorunn

    2016-01-01

    Serious games (exergames) have the potential to be effective for postural balance and increasing muscle strength. Several games have been developed to increase physical fitness and balance among older adults. However, it is unclear to which degree usability and acceptability of exergames for olde...

  5. Bacterial contamination of re-usable laryngoscope blades during the ...

    African Journals Online (AJOL)

    We aimed to assess the level of microbial contamination of re-usable laryngoscope blades at a public hospital in South Africa. Setting. The theatre complex of a secondary-level public hospital in Johannesburg. Methods. Blades from two different theatres were sampled twice daily, using a standardised technique, over a ...

  6. Usability and Utility of a Mobile Application for Marksmanship Training

    Science.gov (United States)

    2015-01-01

    sensitivity, and colour vision data were collected under protocol 2013-073: Automated Target Cueing in Scene Search (Dr. Mackenzie Glaholt, DRDC Toronto... Psychological Science, 1(3), 181- 210. Ryu, Y. S., & Smith-Jackson, T. L. (2006). Reliability and Validity of the Mobile Phone Usability Questionnaire

  7. Improving the Interplay between Usability Evaluation and User Interface Design

    DEFF Research Database (Denmark)

    Hornbæk, K.; Stage, Jan

    2004-01-01

    of the workshop are motivated and an outline of the contents of the papers that were presented in the workshop is given. In addition we summarize some challenges to the interplay between usability evaluation and user interface design agreed upon at the workshop, as well as some solutions that were debated....

  8. Considerations and Methods for Usability Testing with Children

    DEFF Research Database (Denmark)

    Andersen, Malene Hjortboe; Khalid, Md. Saifuddin; Brooks, Eva Irene

    2017-01-01

    of these methods is that they are designed for adults and are not necessarily appropriate to investigations including children. The guiding questions for this systematic literature review are (1) the motivation for conducting usability tests with children, and (2) the kind of methodological, practical, and ethical...

  9. The reliability and usability of district health information software ...

    African Journals Online (AJOL)

    Department of Computer Science, University of Dar-es-Salaam, P.O. Box 35062, Dar-es-Salaam, Tanzania ... in order to assure usability and reduce the incidences and impact of human .... the questions were directed during the DHIS user.

  10. Promise Fulfilled? An EBSCO Discovery Service Usability Study

    Science.gov (United States)

    Williams, Sarah C.; Foster, Anita K.

    2011-01-01

    Discovery tools are the next phase of library search systems. Illinois State University's Milner Library implemented EBSCO Discovery Service in August 2010. The authors conducted usability studies on the system in the fall of 2010. The aims of the study were twofold: first, to determine how Milner users set about using the system in order to…

  11. Impact of usability on efforts to bridge the digital divide

    CSIR Research Space (South Africa)

    Adebesin, F

    2010-11-01

    Full Text Available in these types of development projects, the dream of the providing effective access may remain just that – a dream. This paper highlights the important role that usability plays in the drive towards narrowing the digital divide. We report on the outcome of a...

  12. Digital Resource Exchange About Music (DREAM): Phase 2 Usability Testing

    Science.gov (United States)

    Upitis, Rena; Boese, Karen; Abrami, Philip C.; Anwar, Zaeem

    2015-01-01

    The Digital Resource Exchange About Music (DREAM) is a virtual space for exchanging information about digital learning tools. The purpose of the present study was to determine how users responded to DREAM in the first four months after its public release. This study is the second phase of usability research on DREAM, and was conducted to guide…

  13. Privacy Enhancing Keyboard: Design, Implementation, and Usability Testing

    Directory of Open Access Journals (Sweden)

    Zhen Ling

    2017-01-01

    Full Text Available To protect users from numerous password inference attacks, we invent a novel context aware privacy enhancing keyboard (PEK for Android touch-based devices. Usually PEK would show a QWERTY keyboard when users input text like an email or a message. Nevertheless, whenever users enter a password in the input box on his or her touch-enabled device, a keyboard will be shown to them with the positions of the characters shuffled at random. PEK has been released on the Google Play since 2014. However, the number of installations has not lived up to our expectation. For the purpose of usable security and privacy, we designed a two-stage usability test and performed two rounds of iterative usability testing in 2016 and 2017 summer with continuous improvements of PEK. The observations from the usability testing are educational: (1 convenience plays a critical role when users select an input method; (2 people think those attacks that PEK prevents are remote from them.

  14. Usability evaluation of user interface of thesis title review system

    Science.gov (United States)

    Tri, Y.; Erna, A.; Gellysa, U.

    2018-03-01

    Presentation of programs with user interface that can be accessed online through the website of course greatly provide user benefits. User can easily access the program they need. There are usability values that serve as a benchmark for the success of a user accessible program, ie efficiency, effectiveness, and convenience. These usability values also determine the development of the program for the better use. Therefore, on the review title thesis program that will be implemented in STT Dumai was measured usability evaluation. It aims to see which sides are not yet perfect and need to be improved to improve the performance and utilization of the program. Usability evaluation was measured by using smartPLS software. Database used was the result of respondent questionnaires that include questions about the experience when they used program. The result of a review of thesis title program implemented in STT Dumai has an efficiency value of 22.615, the effectiveness of 20.612, and satisfaction of 33.177.

  15. The role of usability in e-lexicography

    Directory of Open Access Journals (Sweden)

    André H. du Plessis

    2017-05-01

    Full Text Available In the development of the metalexicography, the primary focus of metalexicographers was on the development of printed dictionaries. As technology advances, the focus now shifts towards online and electronic products. Tarp (2009:23–24 posits that this shift results in metalexicographic shortcomings. This means that the theories used to create and evaluate dictionaries are not sufficient anymore. Bergenholtz and Bothma (2011:54 show that dictionaries as data carriers are now not only limited to the field of lexicography, but also to information technological fields. For current lexicographers to be successful in the digital age, the theories used in designing, developing and critiquing dictionaries must adapt with regards to current information technological trends, norms and practices. One aspect that must be addressed is the usability of dictionaries and other electronic lexicographic tools. By using usability theories and standards, current metalexicographical principles can be adapted for the digital age in a streamlined fashion. This study aims to show how usability theories and standards can be advantageous for metalexicography and that future electronic metalexicographic endeavours should not be undertaken without considering the usability as part of the theoretical framework.

  16. APPLICATION OF USABILITY CONCEPTS IN WINE MARKETING: A MULTIDISCIPLINARY REVIEW

    Directory of Open Access Journals (Sweden)

    Cătălina CHIVU-DRAGHIA

    2015-10-01

    Full Text Available Various studies have shown that the wine consumption decline in young generation could be influenced by the perception of wine as intimidating and difficult to understand, and by the lack of adaptability of the product’s communication strategy and packaging design to their lifestyle. Information available on the packaging is often complex and confusing for novice wine consumers and sometimes even irrelevant in regards to the intrinsic characteristics of the product. Furthermore, wine is seen by young adult consumers as old fashion, formal and mostly not associated with their relaxed attitude and “on the move” lifestyle. The objective of this paper is to analyse the usability key principles and heuristic and their applicability in wine marketing as a mean to improve the perception and increase understanding of wine for the young and/or novice consumers. The paper aims to review the existing knowledge and findings about the concept of usability (with special emphasis on Usability Engineering and Human Computer Interaction (HCI, in order to explore the aspects applicable in wine marketing. The usability concept proves useful in wine marketing to simplify the decision process, to make the meeting with the product less intimidating and more engaging, and to decrease the risk perception for the inexperienced wine consumers.

  17. Usability study of youtube websites for Malaysian teenagers

    Science.gov (United States)

    Razak, Mohd Nur Faiz Abd; Hussain, Azham; Hamdi, Mohd Maizan Fishol

    2017-10-01

    Nowadays, YouTube is the 3rd most visited website in the world. It was created for users to search, watch and share video. Statistics show that YouTube run in more than 88 countries and support 76 different languages which covered almost 95% of Internet population globally. Therefore, a usability study is for specific type of users such as based on gender, range of age and country is considered a must for this kind of top website. In this study, we focus on YouTube website usability for Malaysian teenagers that are currently schooling in boarding school with limited access of Internet. It was done in a controlled lab environment with proper devices and software as MacBook, LCD Monitor, and WhatPulse heat map tracker. The evaluation was made based on usability metrics: ease of use, usefulness and satisfaction of users with combination of recording videos, mouse and keyboard heat map and questionnaires. Findings show that most of the respondents just use YouTube for video watching only while ignoring other features in the same time. There are difficulties in using it at the first moment but could catch up in short time. It shows how usable YouTube website especially in the learnability and memorability aspects.

  18. A Usability Study of Interactive Web-Based Modules

    Science.gov (United States)

    Girard, Tulay; Pinar, Musa

    2011-01-01

    This research advances the understanding of the usability of marketing case study modules in the area of interactive web-based technologies through the assignment of seven interactive case modules in a Principles of Marketing course. The case modules were provided for marketing students by the publisher, McGraw Hill Irwin, of the…

  19. Dogmas in the assessment of usability evaluation methods

    DEFF Research Database (Denmark)

    Hornbæk, Kasper

    2010-01-01

    Usability evaluation methods (UEMs) are widely recognised as an essential part of systems development. Assessments of the performance of UEMs, however, have been criticised for low validity and limited reliability. The present study extends this critique by describing seven dogmas in recent work ...... research approaches that may help move beyond the dogmas. In particular, we emphasise detailed studies of evaluation processes, assessments of the impact of UEMs on design carried out in real-world systems development and analyses of how UEMs may be combined......Usability evaluation methods (UEMs) are widely recognised as an essential part of systems development. Assessments of the performance of UEMs, however, have been criticised for low validity and limited reliability. The present study extends this critique by describing seven dogmas in recent work...... on UEMs. The dogmas include using inadequate procedures and measures for assessment, focusing on win-lose outcomes, holding simplistic models of how usability evaluators work, concentrating on evaluation rather than on design and working from the assumption that usability problems are real. We discuss...

  20. Evaluating the usability of web pages: a case study

    NARCIS (Netherlands)

    Lautenbach, M.A.E.; Schegget, I.E. ter; Schoute, A.E.; Witteman, C.L.M.

    1999-01-01

    An evaluation of the Utrecht University website was carried out with 240 students. New criteria were drawn from the literature and operationalized for the study. These criteria are surveyability and findability. Web pages can be said to satisfy a usability criterion if their efficiency and

  1. Usability of consumer-related information sources for design improvement

    NARCIS (Netherlands)

    Thiruvenkadam, G.; Brombacher, A.C.; Lu, Y.; Ouden, den P.H.

    2008-01-01

    In this paper we report the findings of a study intended to assess the usability of consumer related information sources in order to improve the design processes of innovative electronic products. Specifically, an evaluation is done of the quality and content of information that would help product

  2. Security Design Flaws That Affect Usability in Online Banking

    Science.gov (United States)

    Gurlen, Stephanie

    2013-01-01

    As the popularity of online banking Websites has increased, the security of these sites has become increasingly critical as attacks against these sites are on the rise. However, the design decisions made during construction of the sites could make usability more difficult, where the user has difficulty making good security decisions. This study…

  3. Designing Websites for ESL Learners: A Usability Testing Study

    Science.gov (United States)

    Liu, Min; Traphagan, Tomoko; Huh, Jin; Koh, Young Ihn; Choi, Gilok; McGregor, Allison

    2008-01-01

    The purpose of this paper is to report on a usability study for ESL websites conducted to gain insights from learners of English as a second language (ESL) as they interacted with specific sites. Five carefully selected ESL sites were tested by 10 different users generating a total of fifty testing sessions. Two major research questions guided the…

  4. Map-based mobile services design, interaction and usability

    CERN Document Server

    Meng, Liqiu; Winter, Stephan; Popovich, Vasily

    2008-01-01

    This book reports the newest research and technical achievements on the following theme blocks: Design of mobile map services and its constraints; Typology and usability of mobile map services; Visualization solutions on small displays for time-critical tasks; Mobile map users; Interaction and adaptation in mobile environments; and Applications of map-based mobile services.

  5. Usability Evaluation of a Research Repository and Collaboration Web Site

    Science.gov (United States)

    Zhang, Tao; Maron, Deborah J.; Charles, Christopher C.

    2013-01-01

    This article reports results from an empirical usability evaluation of Human-Animal Bond Research Initiative Central as part of the effort to develop an open access research repository and collaboration platform for human-animal bond researchers. By repurposing and altering key features of the original HUBzero system, Human-Animal Bond Research…

  6. Ethical Concerns in Usability Testing Involving Older Adults

    DEFF Research Database (Denmark)

    Møller, Margrethe Hansen

    Based on experience from the research project “User Manuals for Older Adults”, this paper discusses whether there are special ethical concerns with older adults as test persons in a usability test involving the think-aloud method. In this context, older adults are defined as individuals with normal...

  7. Usability and accessibility evaluation of the digital doorway

    CSIR Research Space (South Africa)

    Adebesin, TF

    2011-03-01

    Full Text Available The Digital Doorway (DD) is a non-standard computer system deployed to promote computer literacy amongst underprivileged communities in South Africa. Since its inception there has been no usability evaluation of the software installed on the DD...

  8. Investigating the Usability of Classroom Management Strategies among Elementary Schoolteachers

    Science.gov (United States)

    Briesch, Amy M.; Briesch, Jacquelyn M.; Chafouleas, Sandra M.

    2015-01-01

    Although teachers are often asked to implement classroom interventions to address student behavior, little is known about their perceived usability of many evidence-based strategies. One thousand five elementary schoolteachers completed the Usage Rating Profile-Intervention-Revised (URP-IR) with regard to the use of one of five evidence-based…

  9. Usability Testing in a Library Web Site Redesign Project.

    Science.gov (United States)

    McMullen, Susan

    2001-01-01

    Discusses the need for an intuitive library information gateway to meet users' information needs and describes the process involved in redesigning a library Web site based on experiences at Roger Williams University. Explains usability testing methods that were used to discover how users were interacting with the Web site interface. (Author/LRW)

  10. Usable and accessible websites in SMEs. Challenges for the future

    Directory of Open Access Journals (Sweden)

    Ana Castillo-Díaz, Ph. D.

    2010-01-01

    Full Text Available In an increasingly competitive environment in which Internet occupies a prominent place, transferring a brand from the offline to the online environment has become a vital issue for companies. Usability and accessibility have become crucial to enable adequate online brand communication. Ensuring websites are usable and accessible will facilitate web navigation, will improve the company’s image, and will favour loyalty towards the brand.This article presents the results of an investigation measuring the extent to what small and medium enterprises (SMEs employ usability and accessibility as supporting pillars of brand in the online environment to communicate with their audiences. The results indicate that usability is in fact taken into account by SMEs, but it is seen more as a technological element than as a promotion tool for the brand. Accessibility, on the other hand, is of secondary concern in the design of websites analysed, since they are not certified by any standard and are not fully accessible. Thus, it can be argued that the concern to transmit the brand online is incipient but, currently, SMEs do not take advantage of all the potential offered by the Web.

  11. Maximum Entropy in Drug Discovery

    Directory of Open Access Journals (Sweden)

    Chih-Yuan Tseng

    2014-07-01

    Full Text Available Drug discovery applies multidisciplinary approaches either experimentally, computationally or both ways to identify lead compounds to treat various diseases. While conventional approaches have yielded many US Food and Drug Administration (FDA-approved drugs, researchers continue investigating and designing better approaches to increase the success rate in the discovery process. In this article, we provide an overview of the current strategies and point out where and how the method of maximum entropy has been introduced in this area. The maximum entropy principle has its root in thermodynamics, yet since Jaynes’ pioneering work in the 1950s, the maximum entropy principle has not only been used as a physics law, but also as a reasoning tool that allows us to process information in hand with the least bias. Its applicability in various disciplines has been abundantly demonstrated. We give several examples of applications of maximum entropy in different stages of drug discovery. Finally, we discuss a promising new direction in drug discovery that is likely to hinge on the ways of utilizing maximum entropy.

  12. A continuous usability evaluation of an electronic medication administration record application.

    Science.gov (United States)

    Vicente Oliveros, Noelia; Gramage Caro, Teresa; Pérez Menéndez-Conde, Covadonga; Álvarez-Diaz, Ana María; Martín-Aragón Álvarez, Sagrario; Bermejo Vicedo, Teresa; Delgado Silveira, Eva

    2017-12-01

    The complexity of an electronic medication administration record (eMAR) has been underestimated by most designers in the past. Usability issues, such as poorly designed user application flow in eMAR, are therefore of vital importance, since they can have a negative impact on nursing activities and result in poor outcomes. The purpose of this study was to evaluate the usability of an eMAR application during its development. A usability evaluation was conducted during the development of the eMAR application. Two usability methods were used: a heuristic evaluation complemented by usability testing. Each eMAR application version provided by the vendor was evaluated by 2 hospital pharmacists, who applied the heuristic method. They reviewed the eMAR tasks, detected usability problems and their heuristic violations, and rated the severity of the usability problems. Usability testing was used to assess the final application version by observing how 3 nurses interacted with the application. Thirty-four versions were assessed before the eMAR application was considered usable. During the heuristic evaluation, the usability problems decreased from 46 unique usability problems in version 1 (V1) to 9 in version 34 (V34). In V1, usability problems were categorized into 154 heuristic violations, which decreased to 27 in V34. The average severity rating also decreased from major usability problem (2.96) to no problem (0.23). During usability testing, the 3 nurses did not encounter new usability problems. A thorough heuristic evaluation is a good method for obtaining a usable eMAR application. This evaluation points key areas for improvement and decreases usability problems and their severity. © 2017 John Wiley & Sons, Ltd.

  13. Virtual Reality for Architectural or Territorial Representations: Usability Perceptions

    Directory of Open Access Journals (Sweden)

    Atta Idrawani Zaini

    2017-05-01

    Full Text Available Virtual reality (VR is widely being researched within various aspects of real-world applications. As architecture and urban design are very much adhered to evaluating and designing space, physical representations are deemed as incompetent to deliver a full-scale depiction of a space. Similarly, digital models are very much also limited in that sense. VR can deliver a full-scale virtual environment (VE, tricking users to be immersed in the replicated environment. This is an advantage for the aforementioned design disciplines, as more relatable and realistic depiction of a space can be modelled. The notion of its usability has become important to be understood from the perspective of architecture and urban design. This paper measured the respondents’ perceptions of VR’s usability through measuring its quality of use based on several criteria. The criteria established were the ease of use, usefulness, and satisfaction. Different levels of architectural details were decided as a form of control. A total of N=96 randomly selected respondents from various backgrounds participated in the survey as they were divided into four different group of treatments. Each group experienced a different VE with different level of architectural details. The first section of analysis is a one-sample analysis and the second is a group difference analysis. From the first analysis, it was found that the respondents perceived VR as a usable tool for architectural or territorial representation. Using Kruskal-Wallis test, it was found that there was no statistically significant difference between groups, suggesting that the respondents perceived VR as usable regardless of the level of architectural details. As this paper used perception data based on the quality of use alone, the efficiency of VR system was not measured. Thus, this paper recommends further studies to be conducted on the system’s efficiency to reflect its usability in full extent.

  14. Effect of current on the maximum possible reward.

    Science.gov (United States)

    Gallistel, C R; Leon, M; Waraczynski, M; Hanau, M S

    1991-12-01

    Using a 2-lever choice paradigm with concurrent variable interval schedules of reward, it was found that when pulse frequency is increased, the preference-determining rewarding effect of 0.5-s trains of brief cathodal pulses delivered to the medial forebrain bundle of the rat saturates (stops increasing) at values ranging from 200 to 631 pulses/s (pps). Raising the current lowered the saturation frequency, which confirms earlier, more extensive findings showing that the rewarding effect of short trains saturates at pulse frequencies that vary from less than 100 pps to more than 800 pps, depending on the current. It was also found that the maximum possible reward--the magnitude of the reward at or beyond the saturation pulse frequency--increases with increasing current. Thus, increasing the current reduces the saturation frequency but increases the subjective magnitude of the maximum possible reward.

  15. Evaluasi Human Machine Interface Menggunakan Kriteria Usability Pada Sistem E-learning Perguruan Tinggi

    Directory of Open Access Journals (Sweden)

    Akhmad Qashlim

    2016-01-01

    Full Text Available Integration HMI with usability in user interface design process is a standart of the success of a website. The design process is done through the approach to the end user to find a problem solution of human machine interface phenomena. It can also generate the maximum level of satisfaction and success of implementation of the website. The purpose of this research is to evaluate HMI using usabilitycriteria to know the application of HMI concept in e-learning and provide proposals for improvements to the HMI. Questionnaire Data were processed using a descriptive analysis and methods of CFA to know the variables that are weakest and which indicators have an important role in shaping the research variables. Evaluation results indicate the application concept of HMI in the e-learning had been done but not the maximum. Data analysis of the results obtained that the main problem lies in the accessibility criteria in the meantime indicator latent variables from forming error prevention, learnability, memorability, visibility and accessibility of influential factor loading values indicated significantly (unidimensionalitas in shaping the criteria of latent variables in first-order CFA. The end result of this research is the proposal of improvement as a HMI solution in the form of principles and technicsuser interface design. This solution is focused on the development of standards for the quality of the interface in e-learning systems and not on the digital learning content presented on the e-learning system. Keywords: Descriptive analisis; Human machine interface; Usability; Confirmatory factor analisys; Elearning

  16. Usability Studies in Virtual and Traditional Computer Aided Design Environments for Fault Identification

    Science.gov (United States)

    2017-08-08

    communicate their subjective opinions. Keywords: Usability Analysis; CAVETM (Cave Automatic Virtual Environments); Human Computer Interface (HCI...the differences in interaction when compared with traditional human computer interfaces. This paper provides analysis via usability study methods

  17. Maximum stellar iron core mass

    Indian Academy of Sciences (India)

    60, No. 3. — journal of. March 2003 physics pp. 415–422. Maximum stellar iron core mass. F W GIACOBBE. Chicago Research Center/American Air Liquide ... iron core compression due to the weight of non-ferrous matter overlying the iron cores within large .... thermal equilibrium velocities will tend to be non-relativistic.

  18. Maximum entropy beam diagnostic tomography

    International Nuclear Information System (INIS)

    Mottershead, C.T.

    1985-01-01

    This paper reviews the formalism of maximum entropy beam diagnostic tomography as applied to the Fusion Materials Irradiation Test (FMIT) prototype accelerator. The same formalism has also been used with streak camera data to produce an ultrahigh speed movie of the beam profile of the Experimental Test Accelerator (ETA) at Livermore. 11 refs., 4 figs

  19. Maximum entropy beam diagnostic tomography

    International Nuclear Information System (INIS)

    Mottershead, C.T.

    1985-01-01

    This paper reviews the formalism of maximum entropy beam diagnostic tomography as applied to the Fusion Materials Irradiation Test (FMIT) prototype accelerator. The same formalism has also been used with streak camera data to produce an ultrahigh speed movie of the beam profile of the Experimental Test Accelerator (ETA) at Livermore

  20. A portable storage maximum thermometer

    International Nuclear Information System (INIS)

    Fayart, Gerard.

    1976-01-01

    A clinical thermometer storing the voltage corresponding to the maximum temperature in an analog memory is described. End of the measurement is shown by a lamp switch out. The measurement time is shortened by means of a low thermal inertia platinum probe. This portable thermometer is fitted with cell test and calibration system [fr

  1. Neutron spectra unfolding with maximum entropy and maximum likelihood

    International Nuclear Information System (INIS)

    Itoh, Shikoh; Tsunoda, Toshiharu

    1989-01-01

    A new unfolding theory has been established on the basis of the maximum entropy principle and the maximum likelihood method. This theory correctly embodies the Poisson statistics of neutron detection, and always brings a positive solution over the whole energy range. Moreover, the theory unifies both problems of overdetermined and of underdetermined. For the latter, the ambiguity in assigning a prior probability, i.e. the initial guess in the Bayesian sense, has become extinct by virtue of the principle. An approximate expression of the covariance matrix for the resultant spectra is also presented. An efficient algorithm to solve the nonlinear system, which appears in the present study, has been established. Results of computer simulation showed the effectiveness of the present theory. (author)

  2. The relationship between perceived usability of a beautiful interface and of an ugly interface

    OpenAIRE

    Mohammed, Naitullah; Syed.Mohammed, Mahamood Ur Rahman

    2012-01-01

    The relationship between the perceived usability of a beautiful interface and of an ugly interface is analyzed in this study. This study correlates the visual aesthetics of the website with perceived usability. This research is performed to know the significance of visual aesthetics on perceived usability. A website is designed with two interfaces. One interface is designed by following design guidelines with respect to usability and the other interface is designed without following guideline...

  3. A comparison of usability methods for testing interactive health technologies: Methodological aspects and empirical evidence

    NARCIS (Netherlands)

    Jaspers, Monique W. M.

    2009-01-01

    OBJECTIVE: Usability evaluation is now widely recognized as critical to the success of interactive health care applications. However, the broad range of usability inspection and testing methods available may make it difficult to decide on a usability assessment plan. To guide novices in the

  4. A framework for characterizing usability requirements elicitation and analysis methodologies (UREAM)

    NARCIS (Netherlands)

    Trienekens, J.J.M.; Kusters, R.J.; Mannaert, H.

    2012-01-01

    Dedicated methodologies for the elicitation and analysis of usability requirements have been proposed in literature, usually developed by usability experts. The usability of these approaches by non-expert software engineers is not obvious. In this paper, the objective is to support developers and

  5. Ten factors to consider when developing usability scenarios and tasks for health information technology.

    Science.gov (United States)

    Russ, Alissa L; Saleem, Jason J

    2018-02-01

    The quality of usability testing is highly dependent upon the associated usability scenarios. To promote usability testing as part of electronic health record (EHR) certification, the Office of the National Coordinator (ONC) for Health Information Technology requires that vendors test specific capabilities of EHRs with clinical end-users and report their usability testing process - including the test scenarios used - along with the results. The ONC outlines basic expectations for usability testing, but there is little guidance in usability texts or scientific literature on how to develop usability scenarios for healthcare applications. The objective of this article is to outline key factors to consider when developing usability scenarios and tasks to evaluate computer-interface based health information technologies. To achieve this goal, we draw upon a decade of our experience conducting usability tests with a variety of healthcare applications and a wide range of end-users, to include healthcare professionals as well as patients. We discuss 10 key factors that influence scenario development: objectives of usability testing; roles of end-user(s); target performance goals; evaluation time constraints; clinical focus; fidelity; scenario-related bias and confounders; embedded probes; minimize risks to end-users; and healthcare related outcome measures. For each factor, we present an illustrative example. This article is intended to aid usability researchers and practitioners in their efforts to advance health information technologies. The article provides broad guidance on usability scenario development and can be applied to a wide range of clinical information systems and applications. Published by Elsevier Inc.

  6. Usability laboratories at Philips : supporting research, development, and design for consumer and professional products

    NARCIS (Netherlands)

    Vries, de G.; Gelderen, van T.; Brigham, F.

    1994-01-01

    This paper describes two of the usability laboratories at Philips, discusses practical issues arising from our experience using the facilities, gives an example of a typical usability evaluation, and briefly outlines our vision for the future of the laboratories. Usability tests at Philips can

  7. Are Language Learning Websites Special? Towards a Research Agenda for Discipline-Specific Usability

    Science.gov (United States)

    Shield, Lesley; Kukulska-Hulme, Agnes

    2006-01-01

    With the intention of defining an initial research agenda for discipline-specific factors in the usability of e-learning websites, this article focuses on the example of foreign language learning. First, general notions and concepts of usability are analyzed, and the term "pedagogical usability" is proposed as a means of focusing on the close…

  8. Usability Testing of a Multimedia e-Learning Resource for Electrolyte and Acid-Base Disorders

    Science.gov (United States)

    Davids, Mogamat Razeen; Chikte, Usuf; Grimmer-Somers, Karen; Halperin, Mitchell L.

    2014-01-01

    The usability of computer interfaces may have a major influence on learning. Design approaches that optimize usability are commonplace in the software development industry but are seldom used in the development of e-learning resources, especially in medical education. We conducted a usability evaluation of a multimedia resource for teaching…

  9. Determination of the effectiveness of two methods for usability evaluation using a CPOE medication ordering system

    NARCIS (Netherlands)

    Khajouei, R.; Hasman, A.; Jaspers, M. W. M.

    2011-01-01

    Objectives: To assess the effectiveness of two usability evaluation methods, cognitive walkthrough (CW) and think aloud (TA), for identifying usability problems and to compare the performance of CW and TA in identifying different types of usability problems. Methods: A CW was performed by two

  10. Usability Testing of an Academic Library Web Site: A Case Study.

    Science.gov (United States)

    Battleson, Brenda; Booth, Austin; Weintrop, Jane

    2001-01-01

    Discusses usability testing as a tool for evaluating the effectiveness and ease of use of academic library Web sites; considers human-computer interaction; reviews major usability principles; and explores the application of formal usability testing to an existing site at the University at Buffalo (NY) libraries. (Author/LRW)

  11. Detrimental Effect Elimination of Laser Frequency Instability in Brillouin Optical Time Domain Reflectometer by Using Self-Heterodyne Detection

    Directory of Open Access Journals (Sweden)

    Yongqian Li

    2017-03-01

    Full Text Available A useful method for eliminating the detrimental effect of laser frequency instability on Brillouin signals by employing the self-heterodyne detection of Rayleigh and Brillouin scattering is presented. From the analysis of Brillouin scattering spectra from fibers with different lengths measured by heterodyne detection, the maximum usable pulse width immune to laser frequency instability is obtained to be about 4 µs in a self-heterodyne detection Brillouin optical time domain reflectometer (BOTDR system using a broad-band laser with low frequency stability. Applying the self-heterodyne detection of Rayleigh and Brillouin scattering in BOTDR system, we successfully demonstrate that the detrimental effect of laser frequency instability on Brillouin signals can be eliminated effectively. Employing the broad-band laser modulated by a 130-ns wide pulse driven electro-optic modulator, the observed maximum errors in temperatures measured by the local heterodyne and self-heterodyne detection BOTDR systems are 7.9 °C and 1.2 °C, respectively.

  12. Usability Evaluation Methods for Special Interest Internet Information Services

    Directory of Open Access Journals (Sweden)

    Eva-Maria Schön

    2014-06-01

    Full Text Available The internet provides a wide range of scientific information for different areas of research, used by the related scientific communities. Often the design or architecture of these web pages does not correspond to the mental model of their users. As a result the wanted information is difficult to find. Methods established by Usability Engineering and User Experience can help to increase the appeal of scientific internet information services by analyzing the users’ requirements. This paper describes a procedure to analyze and optimize scientific internet information services that can be accomplished with relatively low effort. It consists of a combination of methods that already have been successfully applied to practice: Personas, usability inspections, Online Questionnaire, Kano model and Web Analytics.

  13. Evaluating the Usability of a Controlled Language Authoring Assistant

    Directory of Open Access Journals (Sweden)

    Miyata Rei

    2017-06-01

    Full Text Available This paper presents experimental results of a usability evaluation of a controlled language (CL authoring assistant designed to help non-professional writers create machine translatable source texts. As the author drafts the text, the system detects CL rule violations and proscribed terms. It also incorporates several support functions to facilitate rephrasing of the source. In order to assess the usability of the system, we conducted a rewriting experiment, in which we compared two groups of participants, one with the aid of the system and the other without it. The results revealed that our system helped reduce the number of CL violations by about 9% and the time to correct violations by more than 30%. The CL-applied source text resulted in higher fluency and adequacy of MT outputs. Questionnaire and interview results also implied the improved satisfaction with the task completion of those participants who used the system.

  14. Usability and user driven innovation - unity or clash?

    DEFF Research Database (Denmark)

    Fronczek-Munter, Aneta

    2011-01-01

    Aim: To present different understandings of the concepts ‗usability‘ and ‗user driven innovation‘ and discuss if and how the built environment can benefit from these concepts and the unity of them. Approach and methodology: The paper is based on literature reviews of scientific journals and other...... influential publications within the academic fields of Facilities Management, Architecture and Engineering, Participatory Design and Software design. Outline: The paper will discuss different understandings of the concept ‗usability‘ and its relation to ‗user driven innovation‘, which depends on the academic...... field and area of professional application. The concept of usability has its roots in evaluations of consumer products and user interfaces of computer software. During the last 5-10 years there has been a new development of research in usability of buildings and workplaces. Recently researchers have...

  15. Testing the Usability of Two Online Research Guides

    Directory of Open Access Journals (Sweden)

    Luigina Vileno

    2011-01-01

    Full Text Available This article describes usability testing of two online research guides. One guide was in the area of applied human sciences and the other was geared toward the discipline of psychology. Six undergraduate students were given several tasks to complete by using the guides. The participants also completed two questionnaires. One described the participants’ demographics and how much time they spent on the Internet on a daily basis. On the other questionnaire, filled out after the usability test, the participants rated the online research guides. Overall, the online research guides were found to be difficult to use. By observing how the participants interacted with the online research guides, the author has identified several problem areas that need to be addressed.

  16. Expanding Usability of Virtual Network Laboratory in IT Engineering Education

    Directory of Open Access Journals (Sweden)

    Dalibor M Dobrilovic

    2013-02-01

    Full Text Available This paper deals with importance of virtual network laboratories usage in IT engineering education. It presents the particular virtual network laboratory model developed for usage in Computer Networks course as well. This virtual network laboratory, called VNLab, is based on virtualization technology. It has been successfully tested in educational process of Computer Network course for IT undergraduate students. Its usability for network related courses is analyzed by comparison of recommended curricula’s of world organizations such as IEEE, ACM and AIS. This paper is focused on expanding the usability of this virtual network laboratory to other non-network related courses. The primary expansion field is in domain of IT System Administration, IT Systems and Data Security and Operating Systems as well. The possible learning scenarios, learning tools and concepts for making this system applicable in these three additional fields are presented by the analyses of compatibility with recommended learning topics and outcomes by IEEE, ACM and AIS.

  17. What makes an automated teller machine usable by blind users?

    Science.gov (United States)

    Manzke, J M; Egan, D H; Felix, D; Krueger, H

    1998-07-01

    Fifteen blind and sighted subjects, who featured as a control group for acceptance, were asked for their requirements for automated teller machines (ATMs). Both groups also tested the usability of a partially operational ATM mock-up. This machine was based on an existing cash dispenser, providing natural speech output, different function menus and different key arrangements. Performance and subjective evaluation data of blind and sighted subjects were collected. All blind subjects were able to operate the ATM successfully. The implemented speech output was the main usability factor for them. The different interface designs did not significantly affect performance and subjective evaluation. Nevertheless, design recommendations can be derived from the requirement assessment. The sighted subjects were rather open for design modifications, especially the implementation of speech output. However, there was also a mismatch of the requirements of the two subject groups, mainly concerning the key arrangement.

  18. Threats or threads: from usable security to secure experience

    DEFF Research Database (Denmark)

    Bødker, Susanne; Mathiasen, Niels Raabjerg

    2008-01-01

    While the domain of security dependent technologies brings new challenges to HCI research it seems that the results and breakthroughs of HCI have not been used in design of security dependent technologies. With exceptions, work in the research field of usable security may be criticized for focusing...... mainly on adjusting user behavior to behave securely. With our background in newer HCI perspectives we address secure interaction from the perspective of security technology as experience. We analyze a number of collected user stories to understand what happens when everyday users encounter security...... dependent technologies. We apply McCarthy & Wright's [12] experience framework to the security domain and our collected stories. We point out that there are significant differences between being secure and having a secure experience, and conclude that classical usable security, focus on people's immediate...

  19. Maximum Water Hammer Sensitivity Analysis

    OpenAIRE

    Jalil Emadi; Abbas Solemani

    2011-01-01

    Pressure waves and Water Hammer occur in a pumping system when valves are closed or opened suddenly or in the case of sudden failure of pumps. Determination of maximum water hammer is considered one of the most important technical and economical items of which engineers and designers of pumping stations and conveyance pipelines should take care. Hammer Software is a recent application used to simulate water hammer. The present study focuses on determining significance of ...

  20. Maximum Gene-Support Tree

    Directory of Open Access Journals (Sweden)

    Yunfeng Shan

    2008-01-01

    Full Text Available Genomes and genes diversify during evolution; however, it is unclear to what extent genes still retain the relationship among species. Model species for molecular phylogenetic studies include yeasts and viruses whose genomes were sequenced as well as plants that have the fossil-supported true phylogenetic trees available. In this study, we generated single gene trees of seven yeast species as well as single gene trees of nine baculovirus species using all the orthologous genes among the species compared. Homologous genes among seven known plants were used for validation of the finding. Four algorithms—maximum parsimony (MP, minimum evolution (ME, maximum likelihood (ML, and neighbor-joining (NJ—were used. Trees were reconstructed before and after weighting the DNA and protein sequence lengths among genes. Rarely a gene can always generate the “true tree” by all the four algorithms. However, the most frequent gene tree, termed “maximum gene-support tree” (MGS tree, or WMGS tree for the weighted one, in yeasts, baculoviruses, or plants was consistently found to be the “true tree” among the species. The results provide insights into the overall degree of divergence of orthologous genes of the genomes analyzed and suggest the following: 1 The true tree relationship among the species studied is still maintained by the largest group of orthologous genes; 2 There are usually more orthologous genes with higher similarities between genetically closer species than between genetically more distant ones; and 3 The maximum gene-support tree reflects the phylogenetic relationship among species in comparison.

  1. LCLS Maximum Credible Beam Power

    International Nuclear Information System (INIS)

    Clendenin, J.

    2005-01-01

    The maximum credible beam power is defined as the highest credible average beam power that the accelerator can deliver to the point in question, given the laws of physics, the beam line design, and assuming all protection devices have failed. For a new accelerator project, the official maximum credible beam power is determined by project staff in consultation with the Radiation Physics Department, after examining the arguments and evidence presented by the appropriate accelerator physicist(s) and beam line engineers. The definitive parameter becomes part of the project's safety envelope. This technical note will first review the studies that were done for the Gun Test Facility (GTF) at SSRL, where a photoinjector similar to the one proposed for the LCLS is being tested. In Section 3 the maximum charge out of the gun for a single rf pulse is calculated. In Section 4, PARMELA simulations are used to track the beam from the gun to the end of the photoinjector. Finally in Section 5 the beam through the matching section and injected into Linac-1 is discussed

  2. Multifunctional systems in vehicles:a usability evaluation

    OpenAIRE

    Rydström, Annie; Bengtsson, Peter; Grane, Camilla; Broström, Robert; Agardh, Johannes; Nilsson, Jennie

    2005-01-01

    Car Human-Machine Interaction (HMI) is becoming increasingly complex as the extension of functionality necessitates new interface concepts. Various multifunctional systems operated by haptic rotary switches, touch screen, and voice control have been developed. A usability study of multifunctional systems available on the market was carried out to evaluate and compare different manual interaction principles. The systems used in the study were the BMW iDrive and the Audi MMI, both operated by a...

  3. Usability of Commercially Available Mobile Applications for Diverse Patients.

    Science.gov (United States)

    Sarkar, Urmimala; Gourley, Gato I; Lyles, Courtney R; Tieu, Lina; Clarity, Cassidy; Newmark, Lisa; Singh, Karandeep; Bates, David W

    2016-12-01

    Mobile applications or 'apps' intended to help people manage their health and chronic conditions are widespread and gaining in popularity. However, little is known about their acceptability and usability for low-income, racially/ethnically diverse populations who experience a disproportionate burden of chronic disease and its complications. The objective of this study was to investigate the usability of existing mobile health applications ("apps") for diabetes, depression, and caregiving, in order to facilitate development and tailoring of patient-facing apps for diverse populations. Usability testing, a mixed-methods approach that includes interviewing and direct observation of participant technology use, was conducted with participants (n = 9 caregivers; n = 10 patients with depression; and n = 10 patients with diabetes) on a total of 11 of the most popular health apps (four diabetes apps, four depression apps, and three caregiver apps) on both iPad and Android tablets. The participants were diverse: 15 (58 %) African Americans, seven (27 %) Whites, two (8 %) Asians, two (8 %) Latinos with either diabetes, depression, or who were caregivers. Participants were given condition-specific tasks, such as entering a blood glucose value into a diabetes app. Participant interviews were video recorded and were coded using standard methods to evaluate attempts and completions of tasks. We performed inductive coding of participant comments to identify emergent themes. Participants completed 79 of 185 (43 %) tasks across 11 apps without assistance. Three themes emerged from participant comments: lack of confidence with technology, frustration with design features and navigation, and interest in having technology to support their self-management. App developers should employ participatory design strategies in order to have an impact on chronic conditions such as diabetes and depression that disproportionately affect vulnerable populations. While patients

  4. Integrated System Validation Usability Questionnaire: Information Display Element

    International Nuclear Information System (INIS)

    Garcés, Ma. I.; Torralba, B.

    2015-01-01

    The Research and Development (R&D) project on “Theoretical and Methodological Approaches to Integrated System Validation of Control Rooms, 2014-2015”, in which the research activities described in this report are framed, has two main objectives: to develop the items for an usability methodology conceived as a part of the measurement framework for performance-based control room evaluation that the OECD Halden Reactor Project will test in the experiments planned for 2015; and the statistical analysis of the data generated in the experimental activities of the Halden Man-Machine Laboratory (HAMMLAB) facility, with previous usability questionnaires, in 2010 and 2011. In this report, the procedure designed to meet the first goal of the project is described, in particular, the process followed to identify the items related to information displays, one of the elements to be included in the usability questionnaire. Three phases are performed, in the first one, the approaches developed by the United States Nuclear Regulatory Commission, NRC, are reviewed and the models proposed by the nuclear energy industry and their technical support organizations, mainly, the United States Electric Power Research Institute, EPRI, are analyzed. In the remaining stages, general and specific guidelines for information displays, in particular, display pages, formats, elements and data quality and update rate recommendations are compared and criteria for the preliminary selection of the items that should be incorporated into the usability questionnaire are defined. This proposal will be reviewed and adapted by the Halden Reactor Project to the design of the specific experiments performed in HAMMLAB.

  5. The Software Therapist: Usability Problem Diagnosis Through Latent Semantic Analysis

    Science.gov (United States)

    2006-06-14

    at a given level is equivalent to removing attributes that don’t apply to a given usability situation, thereby filtering or pruning off irrelevant sub...Each answer prunes the number of stages remaining. Through a process of elimination, the Wizard helps evaluators home in on the correct stage...the diagnosis for one problem report, the user may want to take a break to get a cup of coffee or take a short walk, but when ready to continue with

  6. Usability analysis of indoor map application in a shopping centre

    Science.gov (United States)

    Dewi, R. S.; Hadi, R. K.

    2018-04-01

    Although indoor navigation is still new in Indonesia, its future development is very promising. Similar to the outdoor one, the indoor navigation technology provides several important functions to support route and landmark findings. Furthermore, there is also a need that indoor navigation can support the public safety especially during disaster evacuation process in a building. It is a common that the indoor navigation technologies are built as applications where users can access this technology using their smartphones, tablets, or personal computers. Therefore, a usability analysis is important to ensure the indoor navigation applications can be operated by users with highest functionality. Among several indoor map applications which were available in the market, this study chose to analyse indoor Google Maps due to its availability and popularity in Indonesia. The experiments to test indoor Google Maps was conducted in one of the biggest shopping centre building in Surabaya, Indonesia. The usability was measured by employing System Usability Scale (SUS) questionnaire. The result showed that the SUS score of indoor Google Maps was below the average score of other cellular applications to indicate the users still had high difficulty in operating and learning the features of indoor Google Maps.

  7. Health Websites: Accessibility and Usability for American Sign Language Users

    Science.gov (United States)

    Kushalnagar, Poorna; Naturale, Joan; Paludneviciene, Raylene; Smith, Scott R.; Werfel, Emily; Doolittle, Richard; Jacobs, Stephen; DeCaro, James

    2015-01-01

    To date, there have been efforts towards creating better health information access for Deaf American Sign Language (ASL) users. However, the usability of websites with access to health information in ASL has not been evaluated. Our paper focuses on the usability of four health websites that include ASL videos. We seek to obtain ASL users’ perspectives on the navigation of these ASL-accessible websites, finding the health information that they needed, and perceived ease of understanding ASL video content. ASL users (N=32) were instructed to find specific information on four ASL-accessible websites, and answered questions related to: 1) navigation to find the task, 2) website usability, and 3) ease of understanding ASL video content for each of the four websites. Participants also gave feedback on what they would like to see in an ASL health library website, including the benefit of added captioning and/or signer model to medical illustration of health videos. Participants who had lower health literacy had greater difficulty in finding information on ASL-accessible health websites. This paper also describes the participants’ preferences for an ideal ASL-accessible health website, and concludes with a discussion on the role of accessible websites in promoting health literacy in ASL users. PMID:24901350

  8. Usability requirements for buildings: a case study on primary schools.

    Science.gov (United States)

    Duca, Gabriella

    2012-01-01

    This paper concerns an applied research aimed at applying the concept of usability, as derived form the standard ISO 9241/11, in the filed of building design, namely primary schools. Starting from the concept that space characteristics play a very relevant role in learning performances, the study presented here developed an original methodology for the assessment of effectiveness, efficiency and satisfaction of buildings hosting primary schools, in order to create a school environment better supporting users in their tasks. Research core is the framework of usability requirements and their related markers, indicators and technical specification that has been formulated in order to check compliance of urban area, building, rooms and architectural details with users needs. Therefore, a detailed task analysis of pupils and teacher tasks has been carried out and two questionnaires addressed to a significant users panel have been formulated for satisfaction survey. Lastly, a matrix for an overall reading of gathered data has been set-up and criteria for usability assessment based on that data has been defined. The whole study has been developed within the case study of a primary school in the Naples city centre, whose contents and results are discussed.

  9. Usability in the lifecycle of medical software development

    Directory of Open Access Journals (Sweden)

    Trauzettel Franziska

    2016-09-01

    Full Text Available A close cooperation with users is necessary to ensure that interactive systems are robust, easy to use and accepted. Therefore, in medical technology, standards for usability are of fundamental importance. We investigated with the presented study how the concept of usability is currently understood and implemented in medical software companies. Interviews were conducted with 21 employees of German enterprises. Furthermore we extended an already existing quantitative online survey where 53 companies (including 24 from the health industry sector participated in. Results show that the importance of usability is recognized by most of the respondents. Moreover, a wide variety of methods and approaches is known and implemented for exploring user needs and evaluating system prototypes. However, it was observed that human-centered design activities mainly focus on functionality, risk prevention and accessibility. Hedonic user needs and subjective perceptions (“user experience” still play a minor role. Based on the results, practical requirements are derived and a “best case” for methodological approach is introduced.

  10. Health literacy and usability of clinical trial search engines.

    Science.gov (United States)

    Utami, Dina; Bickmore, Timothy W; Barry, Barbara; Paasche-Orlow, Michael K

    2014-01-01

    Several web-based search engines have been developed to assist individuals to find clinical trials for which they may be interested in volunteering. However, these search engines may be difficult for individuals with low health and computer literacy to navigate. The authors present findings from a usability evaluation of clinical trial search tools with 41 participants across the health and computer literacy spectrum. The study consisted of 3 parts: (a) a usability study of an existing web-based clinical trial search tool; (b) a usability study of a keyword-based clinical trial search tool; and (c) an exploratory study investigating users' information needs when deciding among 2 or more candidate clinical trials. From the first 2 studies, the authors found that users with low health literacy have difficulty forming queries using keywords and have significantly more difficulty using a standard web-based clinical trial search tool compared with users with adequate health literacy. From the third study, the authors identified the search factors most important to individuals searching for clinical trials and how these varied by health literacy level.

  11. Intra- and Inter-Cultural Usability in Computer-Supported Collaboration

    DEFF Research Database (Denmark)

    Vatrapu, Ravi; Suthers, Dan

    2010-01-01

    In this paper, we argue for an increased scope of universal design to encompass usability and accessibility for not only users with physical disabilities but also for users from different cultures. Towards this end, we present an empirical evaluation of cultural usability in computer......-Chinese, and Chinese-Chinese) appropriated affordances and produced technological intersubjectivity. Cultural usability was analyzed through the use of performance and satisfaction measures. The results show a systemic variation in efficiency, effectiveness, and satisfaction between the two cultural groups....... Implications of these findings for the research and practice of usability, in general, and cultural usability, in particular, are discussed in this paper....

  12. THE USABILITY OF PELVEXISER URO-STOP DEVICE

    Directory of Open Access Journals (Sweden)

    Leja Štrukelj

    2018-02-01

    Full Text Available Background:The biofeedback is used as an adjunct to pelvic floor muscle training (PFMT. It includes primarily the vaginal and anal surface electromyography and urethral and vaginal squeeze pressure measurements. However, several systematic reviews concluded that combined therapy seems to have no additional benefit compared to PFMT alone, but might be useful for some women to learn how to perform a correct PFM contraction and to increase motiva- tion. The aim of the study was identify the degree of usability of the Pelvexiser URO-STOP device in raising the awareness and coordinated PFM function, self-learning of correct voluntary PFM contraction and the performance of PFM. Methods: Women between 18 and 65 years of age were invited to participate in the study. The par- ticipants presented with PFM dysfunction which was defined as clinically present urinary incontinence and weak PFM or absence of PFM contraction, respectively. They were referred to physiotherapy by a specialist in gynaecology and obstetrics. In the first physiotherapy session the participants filled in a preliminary questionnaire and received detailed written and verbal instructions on the use of Pelvexiser URO-STOP device (the device measures the change in vaginal squeeze pressure. The PFM function was assessed by visual observation and vaginal palpation. During the assessment the participants were offered no feedback on the correctness/incorrectness of PFM contraction performance. The PFM function was assessed by a modified Oxford scale. The participants used the device for four weeks by themselves at home. After this period they filled in a final questionnaire and their PFM function was re-assessed. Descriptive statistics were used to summarize and analyze the data from the questionnaires, PFMT diaries and the PFM function assessment sheets. Results: Included in the study were 8 female subjects (age 41 (±13 experiencing PFM dysfunction who had given written consent to

  13. Adding SPICE to a Library Internet Site: A Recipe to Enhance Usability

    Directory of Open Access Journals (Sweden)

    Ingrid Tonnison

    2006-03-01

    Full Text Available Objective - To produce a highly- usable intranet site, use the project to explore the practical application of evidence-based librarianship (EBL, and refine the library's project management methodology. Methods - Evidence was gathered via a literature review, an online survey, scenario-based usability testing, and the completion of a usability checlist. Usability issues were then addressed, guided by the Research-Based Web Design and Usability Guidelines. Results - After a preliminary revision, the site achieved a usability index of 79% after application of the "Raward Library Usability Analysis Tool". Finding the information and supporting user tasks were identified as areas of weakness. Usability testing and cleint feedback supported these findings. After these issues were addressed by a major site redeveloment, the usability index increased to 98%. Conclusions - Raward's checklist is an easy and effective tool for measuring and identifying usability issues. Its value was enhanced by scenario-based usability testing, which yielded rich, client specific information. The application of EBL and project management princples ehnanced the outcomes of the project, and the professional development of the project team.

  14. Qualitative review of usability problems in health information systems for radiology.

    Science.gov (United States)

    Dias, Camila Rodrigues; Pereira, Marluce Rodrigues; Freire, André Pimenta

    2017-12-01

    Radiology processes are commonly supported by Radiology Information System (RIS), Picture Archiving and Communication System (PACS) and other software for radiology. However, these information technologies can present usability problems that affect the performance of radiologists and physicians, especially considering the complexity of the tasks involved. The purpose of this study was to extract, classify and analyze qualitatively the usability problems in PACS, RIS and other software for radiology. A systematic review was performed to extract usability problems reported in empirical usability studies in the literature. The usability problems were categorized as violations of Nielsen and Molich's usability heuristics. The qualitative analysis indicated the causes and the effects of the identified usability problems. From the 431 papers initially identified, 10 met the study criteria. The analysis of the papers identified 90 instances of usability problems, classified into categories corresponding to established usability heuristics. The five heuristics with the highest number of instances of usability problems were "Flexibility and efficiency of use", "Consistency and standards", "Match between system and the real world", "Recognition rather than recall" and "Help and documentation", respectively. These problems can make the interaction time consuming, causing delays in tasks, dissatisfaction, frustration, preventing users from enjoying all the benefits and functionalities of the system, as well as leading to more errors and difficulties in carrying out clinical analyses. Furthermore, the present paper showed a lack of studies performed on systems for radiology, especially usability evaluations using formal methods of evaluation involving the final users. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Generic maximum likely scale selection

    DEFF Research Database (Denmark)

    Pedersen, Kim Steenstrup; Loog, Marco; Markussen, Bo

    2007-01-01

    in this work is on applying this selection principle under a Brownian image model. This image model provides a simple scale invariant prior for natural images and we provide illustrative examples of the behavior of our scale estimation on such images. In these illustrative examples, estimation is based......The fundamental problem of local scale selection is addressed by means of a novel principle, which is based on maximum likelihood estimation. The principle is generally applicable to a broad variety of image models and descriptors, and provides a generic scale estimation methodology. The focus...

  16. Extreme Maximum Land Surface Temperatures.

    Science.gov (United States)

    Garratt, J. R.

    1992-09-01

    There are numerous reports in the literature of observations of land surface temperatures. Some of these, almost all made in situ, reveal maximum values in the 50°-70°C range, with a few, made in desert regions, near 80°C. Consideration of a simplified form of the surface energy balance equation, utilizing likely upper values of absorbed shortwave flux (1000 W m2) and screen air temperature (55°C), that surface temperatures in the vicinity of 90°-100°C may occur for dry, darkish soils of low thermal conductivity (0.1-0.2 W m1 K1). Numerical simulations confirm this and suggest that temperature gradients in the first few centimeters of soil may reach 0.5°-1°C mm1 under these extreme conditions. The study bears upon the intrinsic interest of identifying extreme maximum temperatures and yields interesting information regarding the comfort zone of animals (including man).

  17. A Persuasive and Social mHealth Application for Physical Activity: A Usability and Feasibility Study.

    Science.gov (United States)

    Al Ayubi, Soleh U; Parmanto, Bambang; Branch, Robert; Ding, Dan

    2014-05-22

    Advances in smartphones and the wide usage of social networking systems offer opportunities for the development of innovative interventions to promote physical activity. To that end, we developed a persuasive and social mHealth application designed to monitor and motivate users to walk more every day. The objectives of this project were to conduct a focused review on the fundamental characteristics of mHealth for physical activity promotion, to develop an mHealth application that meets such characteristics, and to conduct a feasibility study to deploy the application in everyday life. This project started as an analytical study to review the fundamental characteristics of the technologies used in physical activity monitoring and promotion. Then, it was followed by a technical development of the application. Next, a 4 week deployment was conducted where participants used the application as part of their daily life. A think-aloud method and in-depth semistructured interviews were conducted following the deployment. A qualitative description method was used to thematically analyze the interviews. Feasibility measures included, adherence to the program, user-system interactions, motivation to use, and experience with physical activity and online social interactions. There were seven fundamental characteristics of physical activity monitoring and promotion that were identified, which were then used as a foundation to develop the application. There were fourteen participants that enrolled in the application evaluation. The age range was from 24 to 45; body mass index ranged from 18.5 to 42.98, with 4 of the subjects falling into the category "obese". Half of them were experienced with smartphones, and all were familiar with a social network system. There were thirteen participants that completed the study; one was excluded. Overall, participants gave high scores to almost all of the usability factors examined, with averages of 4.52 out of a 5.00 maximum. Over 29 days

  18. Maximum likelihood window for time delay estimation

    International Nuclear Information System (INIS)

    Lee, Young Sup; Yoon, Dong Jin; Kim, Chi Yup

    2004-01-01

    Time delay estimation for the detection of leak location in underground pipelines is critically important. Because the exact leak location depends upon the precision of the time delay between sensor signals due to leak noise and the speed of elastic waves, the research on the estimation of time delay has been one of the key issues in leak lovating with the time arrival difference method. In this study, an optimal Maximum Likelihood window is considered to obtain a better estimation of the time delay. This method has been proved in experiments, which can provide much clearer and more precise peaks in cross-correlation functions of leak signals. The leak location error has been less than 1 % of the distance between sensors, for example the error was not greater than 3 m for 300 m long underground pipelines. Apart from the experiment, an intensive theoretical analysis in terms of signal processing has been described. The improved leak locating with the suggested method is due to the windowing effect in frequency domain, which offers a weighting in significant frequencies.

  19. Usability testing for the rest of us: the application of discount usability principles in the development of an online communications assessment application.

    Science.gov (United States)

    Brock, Douglas; Kim, Sara; Palmer, Odawni; Gallagher, Thomas; Holmboe, Eric

    2013-01-01

    Usability evaluation provides developers and educators with the means to understand user needs, improve overall product utility, and increase user satisfaction. The application of "discount usability" principles developed to make usability testing more practical and useful may improve user experience at minimal cost and require little existing expertise to conduct. We describe an application of discount usability to a high-fidelity online communications assessment application developed by the University of Washington for the American Board of Internal Medicine. Eight internal medicine physicians completed a discount usability test. Sessions were recorded and the videos analyzed for significant usability concerns. Concerns were identified, summarized, discussed, and prioritized by the authors in collaboration with the software developers before implementing any changes to the interface. Thirty-eight significant usability issues were detected and four technical problems were identified. Each issue was responded to through modification of the software, by providing additional instruction, or delayed for a later version to be developed. Discount usability can be easily implemented in academic developmental activities. Our study resulted in the discovery and remediation of significant user problems, in addition to giving important insight into the novel methods built into the application.

  20. System for memorizing maximum values

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1992-08-01

    The invention discloses a system capable of memorizing maximum sensed values. The system includes conditioning circuitry which receives the analog output signal from a sensor transducer. The conditioning circuitry rectifies and filters the analog signal and provides an input signal to a digital driver, which may be either linear or logarithmic. The driver converts the analog signal to discrete digital values, which in turn triggers an output signal on one of a plurality of driver output lines n. The particular output lines selected is dependent on the converted digital value. A microfuse memory device connects across the driver output lines, with n segments. Each segment is associated with one driver output line, and includes a microfuse that is blown when a signal appears on the associated driver output line.

  1. Remarks on the maximum luminosity

    Science.gov (United States)

    Cardoso, Vitor; Ikeda, Taishi; Moore, Christopher J.; Yoo, Chul-Moon

    2018-04-01

    The quest for fundamental limitations on physical processes is old and venerable. Here, we investigate the maximum possible power, or luminosity, that any event can produce. We show, via full nonlinear simulations of Einstein's equations, that there exist initial conditions which give rise to arbitrarily large luminosities. However, the requirement that there is no past horizon in the spacetime seems to limit the luminosity to below the Planck value, LP=c5/G . Numerical relativity simulations of critical collapse yield the largest luminosities observed to date, ≈ 0.2 LP . We also present an analytic solution to the Einstein equations which seems to give an unboundedly large luminosity; this will guide future numerical efforts to investigate super-Planckian luminosities.

  2. Maximum mutual information regularized classification

    KAUST Repository

    Wang, Jim Jing-Yan

    2014-09-07

    In this paper, a novel pattern classification approach is proposed by regularizing the classifier learning to maximize mutual information between the classification response and the true class label. We argue that, with the learned classifier, the uncertainty of the true class label of a data sample should be reduced by knowing its classification response as much as possible. The reduced uncertainty is measured by the mutual information between the classification response and the true class label. To this end, when learning a linear classifier, we propose to maximize the mutual information between classification responses and true class labels of training samples, besides minimizing the classification error and reducing the classifier complexity. An objective function is constructed by modeling mutual information with entropy estimation, and it is optimized by a gradient descend method in an iterative algorithm. Experiments on two real world pattern classification problems show the significant improvements achieved by maximum mutual information regularization.

  3. Scintillation counter, maximum gamma aspect

    International Nuclear Information System (INIS)

    Thumim, A.D.

    1975-01-01

    A scintillation counter, particularly for counting gamma ray photons, includes a massive lead radiation shield surrounding a sample-receiving zone. The shield is disassembleable into a plurality of segments to allow facile installation and removal of a photomultiplier tube assembly, the segments being so constructed as to prevent straight-line access of external radiation through the shield into radiation-responsive areas. Provisions are made for accurately aligning the photomultiplier tube with respect to one or more sample-transmitting bores extending through the shield to the sample receiving zone. A sample elevator, used in transporting samples into the zone, is designed to provide a maximum gamma-receiving aspect to maximize the gamma detecting efficiency. (U.S.)

  4. Maximum mutual information regularized classification

    KAUST Repository

    Wang, Jim Jing-Yan; Wang, Yi; Zhao, Shiguang; Gao, Xin

    2014-01-01

    In this paper, a novel pattern classification approach is proposed by regularizing the classifier learning to maximize mutual information between the classification response and the true class label. We argue that, with the learned classifier, the uncertainty of the true class label of a data sample should be reduced by knowing its classification response as much as possible. The reduced uncertainty is measured by the mutual information between the classification response and the true class label. To this end, when learning a linear classifier, we propose to maximize the mutual information between classification responses and true class labels of training samples, besides minimizing the classification error and reducing the classifier complexity. An objective function is constructed by modeling mutual information with entropy estimation, and it is optimized by a gradient descend method in an iterative algorithm. Experiments on two real world pattern classification problems show the significant improvements achieved by maximum mutual information regularization.

  5. A Usability Evaluation Model for Academic Library Websites: Efficiency, Effectiveness and Learnability

    Directory of Open Access Journals (Sweden)

    Soohyung Joo

    2011-12-01

    Full Text Available Purpose – This paper aimed to develop a usability evaluation model and associated survey tool in the context of academic libraries. This study not only proposed a usability evaluation model but also a practical survey tool tailored to academic library websites. Design/methodology – A usability evaluation model has been developed for academic library websites based on literature review and expert consultation. Then, the authors verified the reliability and validity of the usability evaluation model empirically using the survey data from actual users. Statistical analysis, such as descriptive statistics, internal consistency test, and a factor analysis, were applied to ensure both the reliability and validity of the usability evaluation tool. Findings – From the document analysis and expert consultation, this study identified eighteen measurement items to survey the three constructs of the usability, effectiveness, efficiency, and learnability, in academic library websites. The evaluation tool was then validated with regard to data distribution, reliability, and validity. The empirical examination based on 147 actual user responses proved the survey evaluation tool suggested herein is acceptable in assessing academic library website usability. Originality/Value – This research is one of the few studies to engender a practical survey tool in evaluating library website usability. The usability model and corresponding survey tool would be useful for librarians and library administrators in academic libraries who plan to conduct a usability evaluation involving large sample.

  6. Using a fuzzy comprehensive evaluation method to determine product usability: A test case.

    Science.gov (United States)

    Zhou, Ronggang; Chan, Alan H S

    2017-01-01

    In order to take into account the inherent uncertainties during product usability evaluation, Zhou and Chan [1] proposed a comprehensive method of usability evaluation for products by combining the analytic hierarchy process (AHP) and fuzzy evaluation methods for synthesizing performance data and subjective response data. This method was designed to provide an integrated framework combining the inevitable vague judgments from the multiple stages of the product evaluation process. In order to illustrate the effectiveness of the model, this study used a summative usability test case to assess the application and strength of the general fuzzy usability framework. To test the proposed fuzzy usability evaluation framework [1], a standard summative usability test was conducted to benchmark the overall usability of a specific network management software. Based on the test data, the fuzzy method was applied to incorporate both the usability scores and uncertainties involved in the multiple components of the evaluation. Then, with Monte Carlo simulation procedures, confidence intervals were used to compare the reliabilities among the fuzzy approach and two typical conventional methods combining metrics based on percentages. This case study showed that the fuzzy evaluation technique can be applied successfully for combining summative usability testing data to achieve an overall usability quality for the network software evaluated. Greater differences of confidence interval widths between the method of averaging equally percentage and weighted evaluation method, including the method of weighted percentage averages, verified the strength of the fuzzy method.

  7. A Fuzzy method for the usability evaluation of nuclear medical equipment

    Energy Technology Data Exchange (ETDEWEB)

    Grecco, Cláudio H.S.; Santos, Isaac J.A.L.; Farias, Marcos S.; Farias, Larissa P.; Filho, Alfredo M.V., E-mail: grecco@ien.gov.br, E-mail: luquetti@ien.gov.br, E-mail: msantana@ien.gov.br, E-mail: larissapfarias@ymail.com, E-mail: marques@ien.gov.br [Instituto de Engenharia Nuclear (DENN/IEN/CNEN/RJ), Rio de Janeiro, RJ (Brazil). Departamento de Engenharia Nuclear

    2017-11-01

    To avoid errors when handling nuclear medical equipment, it is important to develop products with a high degree of usability. This can be achieved by performing usability evaluations in the product development process to detect and mitigate potential usability problems. Usability evaluation focuses on how well users can learn and use a product to achieve their goals. Thus, the usability evaluation has become recognized as a valuable complement to the established approaches to design good user interfaces, to reduce incidents and accidents as well the time required to learn how to use the equipment. To gather information about usability, practitioners use a variety of methods that gather feedback from users about an existing interface or plans related to a new interface. A wide range of usability evaluation methods have been proposed, but few methods focus on developing an objective and practical evaluation method for usability. Moreover, the usability evaluations are based on human judgments and most methods cannot fully solve the subjectivity of these evaluations. In order to remedy this deficiency, the purpose of this work is to adopt a Fuzzy Set Theory (FST) approach to establish a method for the usability evaluation of nuclear medical equipment based on usability heuristics for user interface design and international standards for ergonomics of human-system interaction. To exemplify the method we performed a usability evaluating of the Digital Spectrometer ESP 13004 by testing it with representative users. The results showed that the method is a proactive tool to provide a basis for checking usability of medical device interfaces. (author)

  8. A Fuzzy method for the usability evaluation of nuclear medical equipment

    International Nuclear Information System (INIS)

    Grecco, Cláudio H.S.; Santos, Isaac J.A.L.; Farias, Marcos S.; Farias, Larissa P.; Filho, Alfredo M.V.

    2017-01-01

    To avoid errors when handling nuclear medical equipment, it is important to develop products with a high degree of usability. This can be achieved by performing usability evaluations in the product development process to detect and mitigate potential usability problems. Usability evaluation focuses on how well users can learn and use a product to achieve their goals. Thus, the usability evaluation has become recognized as a valuable complement to the established approaches to design good user interfaces, to reduce incidents and accidents as well the time required to learn how to use the equipment. To gather information about usability, practitioners use a variety of methods that gather feedback from users about an existing interface or plans related to a new interface. A wide range of usability evaluation methods have been proposed, but few methods focus on developing an objective and practical evaluation method for usability. Moreover, the usability evaluations are based on human judgments and most methods cannot fully solve the subjectivity of these evaluations. In order to remedy this deficiency, the purpose of this work is to adopt a Fuzzy Set Theory (FST) approach to establish a method for the usability evaluation of nuclear medical equipment based on usability heuristics for user interface design and international standards for ergonomics of human-system interaction. To exemplify the method we performed a usability evaluating of the Digital Spectrometer ESP 13004 by testing it with representative users. The results showed that the method is a proactive tool to provide a basis for checking usability of medical device interfaces. (author)

  9. The Usability of Online Geographic Virtual Reality for Urban Planning

    Science.gov (United States)

    Zhang, S.; Moore, A. B.

    2013-08-01

    Virtual reality (VR) technology is starting to become widely and freely available (for example the online OpenSimulator tool), with potential for use in 3D urban planning and design tasks but still needing rigorous assessment to establish this. A previous study consulted with a small group of urban professionals, who concluded in a satisfaction usability test that online VR had potential value as a usable 3D communication and remote marketing tool but acknowledged that visual quality and geographic accuracy were obstacles to overcome. This research takes the investigation a significant step further to also examine the usability aspects of efficiency (how quickly tasks are completed) and effectiveness (how successfully tasks are completed), relating to OpenSimulator in an urban planning situation. The comparative study pits a three-dimensional VR model (with increased graphic fidelity and geographic content to address the feedback of the previous study) of a subdivision design (in a Dunedin suburb) against 3D models built with GIS (ArcGIS) and CAD (BricsCAD) tools, two types of software environment well established in urban professional practice. Urban professionals participated in the study by attempting to perform timed tasks correctly in each of the environments before being asked questions about the technologies involved and their perceived importance to their professional work. The results reinforce the positive feedback for VR of the previous study, with the graphical and geographic data issues being somewhat addressed (though participants stressed the need for accurate and precise object and terrain modification capabilities in VR). Ease-ofuse and associated fastest task completion speed were significant positive outcomes to emerge from the comparison with GIS and CAD, pointing to a strong future for VR in an urban planning context.

  10. Usability Analysis within The DataONE Network of Collaborators

    Science.gov (United States)

    Budden, A. E.; Frame, M. T.; Tenopir, C.; Volentine, R.

    2014-12-01

    DataONE was conceived as a 10-year project to enable new science and knowledge creation through universal access to data about life on Earth and the environment that sustains it. In Phase I (2009-2014) more than 300 DataONE participants designed, developed and deployed a robust cyberinfrastructure (CI) with innovative services, and directly engaged and educated a broad stakeholder community. DataONE provides a resilient, scalable infrastructure using Member Nodes (data repositories), Coordinating Nodes, and an Investigator Toolkit to support the data access and data management needs of biological, Earth, and environmental science researchers in the U.S. and across the globe. DataONE collaborators, such as the U.S. Geological Survey, University of New Mexico, and the University of Tennessee, perform research to measure both the current data practices and opinions of DataONE stakeholders and the usability of DataONE for these stakeholders. Stakeholders include scientists, data managers, librarians, and educators among others. The DataONE Usability and Assessment Working Group, which includes members from multiple sectors, does research, development, and implementation projects on DataONE processes, systems, and methods. These projects are essential to insure that DataONE products and services meet network goals, include appropriate community involvement, and demonstrate progress and achievements of DataONE. This poster will provide an overview of DataONE's usability analysis and assessment methodologies, benefits to DataONE and its collaborators, and current tools/techniques being utilized by the participants.

  11. Usability of cerebrospinal fluid biomarkers in a tertiary memory clinic

    DEFF Research Database (Denmark)

    Brandt, C.; Bahl, J.C.; Heegaard, N.H.

    2008-01-01

    AIM: Assays for cerebrospinal fluid (CSF) levels of total tau, phospho-tau protein and beta-amyloid 1-42 have been available for some years. The aim of the study was to assess the usability of these biomarkers in a mixed population of tertiary dementia referral patients in a university-based memory......, the sensitivity of a single abnormal value was between 33 and 66%. The specificity was high except when discriminating AD from amnestic mild cognitive impairment. Two or more abnormal markers further increased the specificity and decreased the sensitivity. CONCLUSION: In a tertiary setting, abnormal CSF biomarker...

  12. Cross-cultural Usability Issues in E/M-Learning

    Directory of Open Access Journals (Sweden)

    Mahdi H. Miraz

    2018-04-01

    Full Text Available This paper gives an overview of electronic learning (E-Learning and mobile learning (M-Learning adoption and diffusion trends, as well as their particular traits, characteristics and issues, especially in terms of cross-cultural and universal usability. E-Learning and M-Learning models using web services and cloud computing, as well as associated security concerns are all addressed. The benefits and enhancements that accrue from using mobile and other internet devices for the purposes of learning in academia are discussed. The differences between traditional classroom-based learning, distance learning, E-Learning and M-Learning models are compared and some conclusions are drawn.

  13. A study of the usability of CGDI in health mapping

    DEFF Research Database (Denmark)

    Gao, Sheng; Mioc, Darka; Xialoun, Yi

    , the development of CGDI has shown great potential in many fields like emergency management, public health, disaster relief, transportation, land information system. Our study is to use CGDI to support online mapping of infectious disease across New Brunswick and Maine and to identify the usability of CGDI...... disease information available to officials and public for better support of disease surveillance, we developed a data model for mapping, seamlessly integrating the spatial and health data across the New Brunswick and Maine border. Many factors such as map representation level, mapping variables, data...

  14. Maximum entropy and Bayesian methods

    International Nuclear Information System (INIS)

    Smith, C.R.; Erickson, G.J.; Neudorfer, P.O.

    1992-01-01

    Bayesian probability theory and Maximum Entropy methods are at the core of a new view of scientific inference. These 'new' ideas, along with the revolution in computational methods afforded by modern computers allow astronomers, electrical engineers, image processors of any type, NMR chemists and physicists, and anyone at all who has to deal with incomplete and noisy data, to take advantage of methods that, in the past, have been applied only in some areas of theoretical physics. The title workshops have been the focus of a group of researchers from many different fields, and this diversity is evident in this book. There are tutorial and theoretical papers, and applications in a very wide variety of fields. Almost any instance of dealing with incomplete and noisy data can be usefully treated by these methods, and many areas of theoretical research are being enhanced by the thoughtful application of Bayes' theorem. Contributions contained in this volume present a state-of-the-art overview that will be influential and useful for many years to come

  15. Usability Metrics for Gamified E-learning Course: A Multilevel Approach

    Directory of Open Access Journals (Sweden)

    Aleksandra Sobodić

    2018-04-01

    Full Text Available This paper discusses the effect of a gamified learning system for students of the master course on Web Design and Programming performed at the Faculty of Organization and Informatics. A new set of usability metrics was derived from web-based learning usability, user experience and instructional design literature and incorporated into the questionnaire which consists of three main categories: Usability, Educational Usability and User Experience. The main contribution of this paper is the development and validation of a questionnaire for measuring the usability of a gamified e-learning course from students’ perspective. Usability practitioners can use the developed metrics with confidence when evaluating the design of a gamified e-learning course in order to improve students’ engagement and motivation.

  16. A human reliability based usability evaluation method for safety-critical software

    International Nuclear Information System (INIS)

    Boring, R. L.; Tran, T. Q.; Gertman, D. I.; Ragsdale, A.

    2006-01-01

    Boring and Gertman (2005) introduced a novel method that augments heuristic usability evaluation methods with that of the human reliability analysis method of SPAR-H. By assigning probabilistic modifiers to individual heuristics, it is possible to arrive at the usability error probability (UEP). Although this UEP is not a literal probability of error, it nonetheless provides a quantitative basis to heuristic evaluation. This method allows one to seamlessly prioritize and identify usability issues (i.e., a higher UEP requires more immediate fixes). However, the original version of this method required the usability evaluator to assign priority weights to the final UEP, thus allowing the priority of a usability issue to differ among usability evaluators. The purpose of this paper is to explore an alternative approach to standardize the priority weighting of the UEP in an effort to improve the method's reliability. (authors)

  17. A Longitudinal Study of Usability in Health Care - Does Time Heal?

    DEFF Research Database (Denmark)

    Kjeldskov, Jesper; Skov, Mikael B.; Stage, Jan

    2007-01-01

    for 15 months, we repeated the evaluation. Our aim was to inquire into the nature of usability problems experienced by novice and expert users, and to see to what extend usability problems of a health care information system may or may not disappear over time, as the nurses get more familiar......We report from a longitudinal laboratory-based usability evaluation of a health care information system. A usability evaluation was conducted with novice users when an electronic patient record system was being deployed in a large hospital. After the nurses had used the system in their daily work...... with it – if time heals poor design. On the basis of our study, we present findings on the usability of the electronic patient system as experienced by the nurses at these two different points in time and discuss implications for evaluating usability in health care....

  18. Usability evaluation of Laboratory and Radiology Information Systems integrated into a hospital information system.

    Science.gov (United States)

    Nabovati, Ehsan; Vakili-Arki, Hasan; Eslami, Saeid; Khajouei, Reza

    2014-04-01

    This study was conducted to evaluate the usability of widely used laboratory and radiology information systems. Three usability experts independently evaluated the user interfaces of Laboratory and Radiology Information Systems using heuristic evaluation method. They applied Nielsen's heuristics to identify and classify usability problems and Nielsen's severity rating to judge their severity. Overall, 116 unique heuristic violations were identified as usability problems. In terms of severity, 67 % of problems were rated as major and catastrophic. Among 10 heuristics, "consistency and standards" was violated most frequently. Moreover, mean severity of problems concerning "error prevention" and "help and documentation" heuristics was higher than of the others. Despite widespread use of specific healthcare information systems, they suffer from usability problems. Improving the usability of systems by following existing design standards and principles from the early phased of system development life cycle is recommended. Especially, it is recommended that the designers design systems that inhibit the initiation of erroneous actions and provide sufficient guidance to users.

  19. Evaluating Distributed Usability: the role of user interfaces in an activity system

    Directory of Open Access Journals (Sweden)

    Lejla Vrazalic

    2003-11-01

    Full Text Available Traditional definitions of usability localise this fundamental Human Computer Interaction (HCI concept in the user interface and reduce it to a variety of qualitative and quantitative attributes of the computer system. This simplistic view of usability has been used as the basis for developing design and evaluation methods in the discipline. This paper argues that, as a result, HCI methods are ineffective and suffer from various shortcomings. It is proposed that the notion of usability must be extended to include contextual factors, and viewed as being distributed across an activity system. Adopting this notion of distributed usability then requires a review of existing HCI methods. Usability testing, as a complete and self-contained HCI method, was chosen for this purpose, and the result, a distributed usability evaluation method (DUEM, is presented in this paper.

  20. From Usability Testing to Clinical Simulations: Bringing Context into the Design and Evaluation of Usable and Safe Health Information Technologies

    DEFF Research Database (Denmark)

    Kushniruk, Andre; Nøhr, Christian; Jensen, Sanne

    2013-01-01

    of clinical context into stronger focus. This involves testing of systems with representative users doing representative tasks, in representative settings/environments. Results: Application of methods where realistic clinical scenarios are used to drive the study of users interacting with systems under...... such evaluation can be used to improve both the usability and safety of HIT. In addition, recent work has shown that clinical simulations, in particular those conducted in-situ, can lead to considerable benefits when compared to the costs of running such studies. Conclusion: In order to bring context of use...

  1. The usability issues of faceted navigation in digital libraries

    Directory of Open Access Journals (Sweden)

    Eliane Blumer

    2014-05-01

    For more than five years, the project ACCEPT, a subproject of a Swiss national project called e-lib.ch, analyzes the usability and usefulness of digital libraries, by using user oriented methods. Experience has shown that filters provided through faceted navigation are considered as positive and very useful by end users. Nevertheless, based on different test results, several returning mistakes have been detected and it turns out that there are some ‘unwritten standards’ concerning e.g. position, labelling or ranking which should be respected to fulfil the aim of a good usability which users do expect of such web services. In this poster we will first give an introduction to faceted navigation, actual design issues and their use in digital libraries and then present testing methods, which can be easily applied in a digital library context. Together with a list of best practices concerning faceted navigation drawn out of different test experiences, the paper should give the reader all important information to evaluate its current faceted navigation and see where improvements could be made.

  2. Usability study of a vineyard teleoperated compost spreader.

    Science.gov (United States)

    Ferrari, Ester; Cavallo, Eugenio

    2012-01-01

    Teleoperation has been widely applied in modern industry because of a variety of advantages, such as providing replaceable surrogates for humans in dangerous or difficult working environments over long distances. In this paper, a usability evaluation study of a teleoperation system for a compost spreader robotic machine is presented. The machine has been designed for the application of compost in small and stepping parcels of hilly vineyards. Driving and working tasks can be controlled remotely by a portable piloting unit, reducing the risk for the operator in the event of machine overturning. Participants of the study were asked to perform a series of tasks and sub-tasks and to vocalize their thoughts while working with the machine. The tasks were designed to simulate typical user experience. Once all the tasks were accomplished each participant was asked to fill a questionnaire. The evaluation considered aspects such as learnability, ease of use, understandability, controllability, frustration, mental effort, distraction, clarity of presentation, perceived usefulness, temporal efficiency and machine aesthetic. Results show that usability evaluation helped detecting design deficiencies in the teleoperated compost spreader machine.

  3. Evaluating the Usability of Authoring Environments for Serious Games.

    Science.gov (United States)

    Slootmaker, Aad; Hummel, Hans; Koper, Rob

    2017-08-01

    Background . The EMERGO method and online platform enable the development and delivery of scenario-based serious games that foster students to acquire professional competence. One of the main goals of the platform is to provide a user-friendly authoring environment for creating virtual environments where students can perform authentic tasks. Aim . We present the findings of an in-depth qualitative case study of the platform's authoring environment and compare our findings on usability with those found for comparable environments in literature. Method . We carried out semi-structured interviews, with two experienced game developers who have authored a game for higher education, and a literature review of comparable environments. Findings . The analysis shows that the usability of the authoring environment is problematic, especially regarding understandability and learnability , which is in line with findings of comparable environments. Other findings are that authoring is well integrated with the EMERGO method and that functionality and reliability of the authoring environment are valued. Practical implications . The lessons learned are presented in the form of general guidelines to improve the understandability and learnability of authoring environments for serious games .

  4. Usability evaluation of in-housed developed ERP system

    Science.gov (United States)

    Faisal, Chaudhry Muhammad Nadeem; Shakeel Faridi, Muhammad; Javed, Zahid

    2011-10-01

    Enterprise Resource Planning systems are the combination of different business IS (Information System) applications that are designed according to the organization requirements. Generally ERP systems are suffering from complex user interface issues. Recent research shows that there is a need for improvement concerning, the user interface from their perspectives. In order to design the software applications that are easy to use, memorize and apply to new problems, we must know the users philosophy and something about learning, reminiscence and problems solving. The Usability engineering is the only way to study the deeds of users while interacting with ERP (Enterprise Resource & Planning). This paper will focus on the users' experiences view of financial module in ERP system. The HCI research method, explicitly survey questionnaire method was adopted to gather users understanding in order to evaluate the selected modules for in-housed ERP system. The study involved group of users from two industries, the results can not be generalized as a whole. The study was first time successfully applied Usability evaluation on in-housed ERP in local industry (Masood Textile Mills, Interloop Ltd) in Pakistan. The results may hopefully opened-up an area of research and methodology that could provide considerable further benefits to Industry in developments of Industrial information systems.

  5. Forensic botany: usability of bryophyte material in forensic studies.

    Science.gov (United States)

    Virtanen, Viivi; Korpelainen, Helena; Kostamo, Kirsi

    2007-10-25

    Two experiments were performed to test the relevance of bryophyte (Plantae, Bryophyta) material for forensic studies. The first experiment was conducted to reveal if, and how well, plant fragments attach to footwear in general. In the test, 16 persons walked outdoors wearing rubber boots or hiking boots. After 24h of use outdoors the boots were carefully cleaned, and all plant fragments were collected. Afterwards, all plant material was examined to identify the species. In the second experiment, fresh material of nine bryophyte species was kept in a shed in adverse conditions for 18 months, after which DNA was extracted and subjected to genotyping to test the quality of the material. Both experiments give support for the usability of bryophyte material in forensic studies. The bryophyte fragments become attached to shoes, where they remain even after the wearer walks on a dry road for several hours. Bryophyte DNA stays intact, allowing DNA profiling after lengthy periods following detachment from the original plant source. Based on these experiments, and considering the fact that many bryophytes are clonal plants, we propose that bryophytes are among the most usable plants to provide botanical evidence for forensic investigations.

  6. Variable frequency iteration MPPT for resonant power converters

    Science.gov (United States)

    Zhang, Qian; Bataresh, Issa; Chen, Lin

    2015-06-30

    A method of maximum power point tracking (MPPT) uses an MPPT algorithm to determine a switching frequency for a resonant power converter, including initializing by setting an initial boundary frequency range that is divided into initial frequency sub-ranges bounded by initial frequencies including an initial center frequency and first and second initial bounding frequencies. A first iteration includes measuring initial powers at the initial frequencies to determine a maximum power initial frequency that is used to set a first reduced frequency search range centered or bounded by the maximum power initial frequency including at least a first additional bounding frequency. A second iteration includes calculating first and second center frequencies by averaging adjacent frequent values in the first reduced frequency search range and measuring second power values at the first and second center frequencies. The switching frequency is determined from measured power values including the second power values.

  7. The evaluation for the usability of the Varian Standard Couch modelingusing Treatment Planning System

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yong Mo; Song, Yong Min; Kim, Jin Man; Choi, Ji Min; Choi, Byeung Gi [Dept. of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of)

    2016-06-15

    When a radiation treatment, there is an attenuation by Carbon Fiber Couch. In this study, we tried to evaluate the usability of the Varian Standard Couch(VSC) by modeling with Treatment Planning System (TPS) VSC was scanned by CBCT(Cone Beam Computed Tomography) of the Linac(Clinac IX, VARIAN, USA), following the three conditions of VSC, Side Rail OutGrid(SROG), Side Rail InGrid(SRIG), Side Rail In OutSpine Down Bar(SRIOS). After scan, the data was transferred to TPS and modeled by contouring Side Rail, Side Bar Upper, Side Bar Lower, Spine Down Bar automatically. We scanned the Cheese Phantom(Middelton, USA) using Computed Tomography(Light Speed RT 16, GE, USA) and transfer the data to TPS, and apply VSC modeled previously with TPS to it. Dose was measured at the isocenter of Ion Chamber(A1SL, Standard imaging, USA) in Cheese Phantom using 4 and 10 MV radiation for every 5° gantry angle in a different filed size(3 X 3 cm{sup 2},10 X 10cm{sup 2}) without any change of MU(=100), and then we compared the calculated dose and measured dose. Also we included dose at the 127° in SRIG to compare the attenuation by Side Bar Upper. Results : The density of VSC by CBCT in TPS was 0.9g/cm{sup 3}, and in the case of Spine Down Bar, it was 0.7g/cm{sup 3}. The radiation was attenuated by 17.49%, 16.49%, 8.54%, and 7.59% at the Side Rail, Side Bar Upper, Side Bar Lower, and Spine Down Bar. For the accuracy of modeling, calculated dose and measured dose were compared. The average error was 1.13% and the maximum error was 1.98% at the 170° beam crossing the Spine Down Bar. To evaluate the usability for the VSC modeled by TPS, the maximum error was 1.98% as a result of compassion between calculated dose and measured dose. We found out that VSC modeling helped expect the dose, so we think that it will be helpful for the more accurate treatment.

  8. Determining Reliability and Validity of the Persian Version of Software Usability Measurements Inventory (SUMI) Questionnaire

    OpenAIRE

    seyed abolfazl zakerian; Roya Azizi; Mehdi Rahgozar

    2013-01-01

    The term usability refers to a special index for success of an operating system. This study aimed to determine the reliability and validity of the Software Usability Measurements Inventory (SUMI) questionnaire as one of the valid and common questionnaires about usability evaluation. The back translation method was used to translate the questionnaire from English to Persian back to English. Moreover, repeatability or test-retest reliability was practically used to determine the reliability of ...

  9. Exploring the Usability of Mobile Apps Supporting Radiologists' Training in Diagnostic Decision Making.

    Science.gov (United States)

    Kim, Min Soon; Aro, Michael R; Lage, Kraig J; Ingalls, Kevin L; Sindhwani, Vivek; Markey, Mia K

    2016-03-01

    The objective of this study was to conduct a usability evaluation of mobile apps for supporting education and training in radiologic diagnostic decision-making processes. Of 381 mobile apps available at two major stores (Google Play and iTunes), eight iOS apps were selected for laboratory-based usability tests. Six staff radiologists completed eight app-specific task sets, using a think-aloud strategy. The triangular methods approach included quantitative performance measures, System Usability Scale (SUS), and qualitative thematic analysis using heuristic usability principles of usability issues. Overall, radiologists achieved higher than 70% success, with favorable SUS scores, in completing the tasks for seven of the eight apps. However, task success rate and SUS score had a weak relation (r = 0.23), indicating that the perceived usability may not reflect the holistic usability of the app. Task analysis and self-report revealed 108 usability issues, which were condensed to 55 unique issues and categorized by nine usability themes and mapped to ten usability heuristics. Nonintuitive functionality (eg, nonintuitive or misleading labels) was the most frequent theme observed, leading to inefficient navigation. These usability findings were consistent with the 13 improvements the radiologists suggested. This study demonstrates the feasibility of usability evaluation of radiology mobile apps and suggests potential improvements in the development of radiology mobile apps. This study also suggests that proficiency with mobile devices may not be equivalent to being an expert user, proficient in using the apps. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  10. Maximum entropy principal for transportation

    International Nuclear Information System (INIS)

    Bilich, F.; Da Silva, R.

    2008-01-01

    In this work we deal with modeling of the transportation phenomenon for use in the transportation planning process and policy-impact studies. The model developed is based on the dependence concept, i.e., the notion that the probability of a trip starting at origin i is dependent on the probability of a trip ending at destination j given that the factors (such as travel time, cost, etc.) which affect travel between origin i and destination j assume some specific values. The derivation of the solution of the model employs the maximum entropy principle combining a priori multinomial distribution with a trip utility concept. This model is utilized to forecast trip distributions under a variety of policy changes and scenarios. The dependence coefficients are obtained from a regression equation where the functional form is derived based on conditional probability and perception of factors from experimental psychology. The dependence coefficients encode all the information that was previously encoded in the form of constraints. In addition, the dependence coefficients encode information that cannot be expressed in the form of constraints for practical reasons, namely, computational tractability. The equivalence between the standard formulation (i.e., objective function with constraints) and the dependence formulation (i.e., without constraints) is demonstrated. The parameters of the dependence-based trip-distribution model are estimated, and the model is also validated using commercial air travel data in the U.S. In addition, policy impact analyses (such as allowance of supersonic flights inside the U.S. and user surcharge at noise-impacted airports) on air travel are performed.

  11. Comparison of CTA and Textual Feedback in Usability Testing for Malaysian Users

    DEFF Research Database (Denmark)

    Sivaji, Ashok; Clemmensen, Torkil; Nielsen, Søren Feodor

    Usability moderators found that the concurrent think-aloud (CTA) method has some cultural limitation that impacts usability testing with Malaysian users. This gives rise to proposing a new method called textual feedback. The research question is to determine whether there are any differences...... in usability defects from the concurrent think-aloud (CTA) method (Condition 2) and textual feedback method (Condition 1) within the same group of Malaysian users. A pair-wise t-test was used, whereby users were subjected to performing usability task using both methods. Results reveal that we can reject...

  12. Use Case Evaluation (UCE): A Method for Early Usability Evaluation in Software Development

    DEFF Research Database (Denmark)

    Stage, Jan; Høegh, Rune Thaarup; Hornbæk, K.

    2007-01-01

    t is often argued that usability problems should be identified as early as possible during software development, but many usability evaluation methods do not fit well in early development activities. We propose a method for usability evaluation of use cases, a widely used representation of design...... ideas produced early in software development processes. The method proceeds by systematic inspection of use cases with reference to a set of guidelines for usable design. To validate the method, four evaluators inspected a set of use cases for a health care application....

  13. OPTIMIZING USABILITY OF AN ECONOMIC DECISION SUPPORT TOOL: PROTOTYPE OF THE EQUIPT TOOL.

    Science.gov (United States)

    Cheung, Kei Long; Hiligsmann, Mickaël; Präger, Maximilian; Jones, Teresa; Józwiak-Hagymásy, Judit; Muñoz, Celia; Lester-George, Adam; Pokhrel, Subhash; López-Nicolás, Ángel; Trapero-Bertran, Marta; Evers, Silvia M A A; de Vries, Hein

    2018-01-01

    Economic decision-support tools can provide valuable information for tobacco control stakeholders, but their usability may impact the adoption of such tools. This study aims to illustrate a mixed-method usability evaluation of an economic decision-support tool for tobacco control, using the EQUIPT ROI tool prototype as a case study. A cross-sectional mixed methods design was used, including a heuristic evaluation, a thinking aloud approach, and a questionnaire testing and exploring the usability of the Return of Investment tool. A total of sixty-six users evaluated the tool (thinking aloud) and completed the questionnaire. For the heuristic evaluation, four experts evaluated the interface. In total twenty-one percent of the respondents perceived good usability. A total of 118 usability problems were identified, from which twenty-six problems were categorized as most severe, indicating high priority to fix them before implementation. Combining user-based and expert-based evaluation methods is recommended as these were shown to identify unique usability problems. The evaluation provides input to optimize usability of a decision-support tool, and may serve as a vantage point for other developers to conduct usability evaluations to refine similar tools before wide-scale implementation. Such studies could reduce implementation gaps by optimizing usability, enhancing in turn the research impact of such interventions.

  14. The current status of usability studies of information technologies in China: a systematic study.

    Science.gov (United States)

    Lei, Jianbo; Xu, Lufei; Meng, Qun; Zhang, Jiajie; Gong, Yang

    2014-01-01

    To systematically review and analyze the current status and characteristics of usability studies in China in the field of information technology in general and in the field of healthcare in particular. We performed a quantitative literature analysis in three major Chinese academic databases and one English language database using Chinese search terms equivalent to the concept of usability. Six hundred forty-seven publications were selected for analysis. We found that in China the literature on usability in the field of information technology began in 1994 and increased thereafter. The usability definitions from ISO 9241-11:1998 and Nielsen (1993) have been widely recognized and cited. Authors who have published several publications are rare. Fourteen journals have a publishing rate over 1%. Only nine publications about HIT were identified. China's usability research started relatively late. There is a lack of organized research teams and dedicated usability journals. High-impact theoretical studies are scarce. On the application side, no original and systematic research frameworks have been developed. The understanding and definition of usability is not well synchronized with international norms. Besides, usability research in HIT is rare. More human and material resources need to be invested in China's usability research, particularly in HIT.

  15. Design and validation of a questionnaire to evaluate the usability of computerized critical care information systems.

    Science.gov (United States)

    von Dincklage, Falk; Lichtner, Gregor; Suchodolski, Klaudiusz; Ragaller, Maximilian; Friesdorf, Wolfgang; Podtschaske, Beatrice

    2017-08-01

    The implementation of computerized critical care information systems (CCIS) can improve the quality of clinical care and staff satisfaction, but also holds risks of disrupting the workflow with consecutive negative impacts. The usability of CCIS is one of the key factors determining their benefits and weaknesses. However, no tailored instrument exists to measure the usability of such systems. Therefore, the aim of this study was to design and validate a questionnaire that measures the usability of CCIS. Following a mixed-method design approach, we developed a questionnaire comprising two evaluation models to assess the usability of CCIS: (1) the task-specific model rates the usability individually for several tasks which CCIS could support and which we derived by analyzing work processes in the ICU; (2) the characteristic-specific model rates the different aspects of the usability, as defined by the international standard "ergonomics of human-system interaction". We tested validity and reliability of the digital version of the questionnaire in a sample population. In the sample population of 535 participants both usability evaluation models showed a strong correlation with the overall rating of the system (multiple correlation coefficients ≥0.80) as well as a very high internal consistency (Cronbach's alpha ≥0.93). The novel questionnaire is a valid and reliable instrument to measure the usability of CCIS and can be used to study the influence of the usability on their implementation benefits and weaknesses.

  16. Users' performance in lab and non-lab environments through online usability testing:A case of evaluating the usability of digital academic libraries' websites

    OpenAIRE

    Alharbi, Abeer; Mayhew, Pam

    2015-01-01

    The factors related to the environment in which users operate may be of a vital importance when trying to understand how they experience a particular system. It is required that we find out how we can get to know those factors to investigate if they affect the users' performance in usability testing. An online usability study has emerged that can be attempted by a large, varied pool of users' anywhere with an Internet connection. Would the usage of an online usability study help to give compr...

  17. Estimating the maximum potential revenue for grid connected electricity storage :

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, Raymond Harry; Silva Monroy, Cesar Augusto.

    2012-12-01

    The valuation of an electricity storage device is based on the expected future cash flow generated by the device. Two potential sources of income for an electricity storage system are energy arbitrage and participation in the frequency regulation market. Energy arbitrage refers to purchasing (stor- ing) energy when electricity prices are low, and selling (discharging) energy when electricity prices are high. Frequency regulation is an ancillary service geared towards maintaining system frequency, and is typically procured by the independent system operator in some type of market. This paper outlines the calculations required to estimate the maximum potential revenue from participating in these two activities. First, a mathematical model is presented for the state of charge as a function of the storage device parameters and the quantities of electricity purchased/sold as well as the quantities o ered into the regulation market. Using this mathematical model, we present a linear programming optimization approach to calculating the maximum potential revenue from an elec- tricity storage device. The calculation of the maximum potential revenue is critical in developing an upper bound on the value of storage, as a benchmark for evaluating potential trading strate- gies, and a tool for capital nance risk assessment. Then, we use historical California Independent System Operator (CAISO) data from 2010-2011 to evaluate the maximum potential revenue from the Tehachapi wind energy storage project, an American Recovery and Reinvestment Act of 2009 (ARRA) energy storage demonstration project. We investigate the maximum potential revenue from two di erent scenarios: arbitrage only and arbitrage combined with the regulation market. Our analysis shows that participation in the regulation market produces four times the revenue compared to arbitrage in the CAISO market using 2010 and 2011 data. Then we evaluate several trading strategies to illustrate how they compare to the

  18. Last Glacial Maximum Salinity Reconstruction

    Science.gov (United States)

    Homola, K.; Spivack, A. J.

    2016-12-01

    It has been previously demonstrated that salinity can be reconstructed from sediment porewater. The goal of our study is to reconstruct high precision salinity during the Last Glacial Maximum (LGM). Salinity is usually determined at high precision via conductivity, which requires a larger volume of water than can be extracted from a sediment core, or via chloride titration, which yields lower than ideal precision. It has been demonstrated for water column samples that high precision density measurements can be used to determine salinity at the precision of a conductivity measurement using the equation of state of seawater. However, water column seawater has a relatively constant composition, in contrast to porewater, where variations from standard seawater composition occur. These deviations, which affect the equation of state, must be corrected for through precise measurements of each ion's concentration and knowledge of apparent partial molar density in seawater. We have developed a density-based method for determining porewater salinity that requires only 5 mL of sample, achieving density precisions of 10-6 g/mL. We have applied this method to porewater samples extracted from long cores collected along a N-S transect across the western North Atlantic (R/V Knorr cruise KN223). Density was determined to a precision of 2.3x10-6 g/mL, which translates to salinity uncertainty of 0.002 gms/kg if the effect of differences in composition is well constrained. Concentrations of anions (Cl-, and SO4-2) and cations (Na+, Mg+, Ca+2, and K+) were measured. To correct salinities at the precision required to unravel LGM Meridional Overturning Circulation, our ion precisions must be better than 0.1% for SO4-/Cl- and Mg+/Na+, and 0.4% for Ca+/Na+, and K+/Na+. Alkalinity, pH and Dissolved Inorganic Carbon of the porewater were determined to precisions better than 4% when ratioed to Cl-, and used to calculate HCO3-, and CO3-2. Apparent partial molar densities in seawater were

  19. Maximum Parsimony on Phylogenetic networks

    Science.gov (United States)

    2012-01-01

    Background Phylogenetic networks are generalizations of phylogenetic trees, that are used to model evolutionary events in various contexts. Several different methods and criteria have been introduced for reconstructing phylogenetic trees. Maximum Parsimony is a character-based approach that infers a phylogenetic tree by minimizing the total number of evolutionary steps required to explain a given set of data assigned on the leaves. Exact solutions for optimizing parsimony scores on phylogenetic trees have been introduced in the past. Results In this paper, we define the parsimony score on networks as the sum of the substitution costs along all the edges of the network; and show that certain well-known algorithms that calculate the optimum parsimony score on trees, such as Sankoff and Fitch algorithms extend naturally for networks, barring conflicting assignments at the reticulate vertices. We provide heuristics for finding the optimum parsimony scores on networks. Our algorithms can be applied for any cost matrix that may contain unequal substitution costs of transforming between different characters along different edges of the network. We analyzed this for experimental data on 10 leaves or fewer with at most 2 reticulations and found that for almost all networks, the bounds returned by the heuristics matched with the exhaustively determined optimum parsimony scores. Conclusion The parsimony score we define here does not directly reflect the cost of the best tree in the network that displays the evolution of the character. However, when searching for the most parsimonious network that describes a collection of characters, it becomes necessary to add additional cost considerations to prefer simpler structures, such as trees over networks. The parsimony score on a network that we describe here takes into account the substitution costs along the additional edges incident on each reticulate vertex, in addition to the substitution costs along the other edges which are

  20. Distributed usability evaluation of the Pennsylvania Cancer Atlas.

    Science.gov (United States)

    Bhowmick, Tanuka; Robinson, Anthony C; Gruver, Adrienne; MacEachren, Alan M; Lengerich, Eugene J

    2008-07-11

    The Pennsylvania Cancer Atlas (PA-CA) is an interactive online atlas to help policy-makers, program managers, and epidemiologists with tasks related to cancer prevention and control. The PA-CA includes maps, graphs, tables, that are dynamically linked to support data exploration and decision-making with spatio-temporal cancer data. Our Atlas development process follows a user-centered design approach. To assess the usability of the initial versions of the PA-CA, we developed and applied a novel strategy for soliciting user feedback through multiple distributed focus groups and surveys. Our process of acquiring user feedback leverages an online web application (e-Delphi). In this paper we describe the PA-CA, detail how we have adapted e-Delphi web application to support usability and utility evaluation of the PA-CA, and present the results of our evaluation. We report results from four sets of users. Each group provided structured individual and group assessments of the PA-CA as well as input on the kinds of users and applications for which it is best suited. Overall reactions to the PA-CA are quite positive. Participants did, however, provide a range of useful suggestions. Key suggestions focused on improving interaction functions, enhancing methods of temporal analysis, addressing data issues, and providing additional data displays and help functions. These suggestions were incorporated in each design and implementation iteration for the PA-CA and used to inform a set of web-atlas design principles. For the Atlas, we find that a design that utilizes linked map, graph, and table views is understandable to and perceived to be useful by the target audience of cancer prevention and control professionals. However, it is clear that considerable variation in experience using maps and graphics exists and for those with less experience, integrated tutorials and help features are needed. In relation to our usability assessment strategy, we find that our distributed, web

  1. Distributed usability evaluation of the Pennsylvania Cancer Atlas

    Directory of Open Access Journals (Sweden)

    MacEachren Alan M

    2008-07-01

    Full Text Available Abstract Background The Pennsylvania Cancer Atlas (PA-CA is an interactive online atlas to help policy-makers, program managers, and epidemiologists with tasks related to cancer prevention and control. The PA-CA includes maps, graphs, tables, that are dynamically linked to support data exploration and decision-making with spatio-temporal cancer data. Our Atlas development process follows a user-centered design approach. To assess the usability of the initial versions of the PA-CA, we developed and applied a novel strategy for soliciting user feedback through multiple distributed focus groups and surveys. Our process of acquiring user feedback leverages an online web application (e-Delphi. In this paper we describe the PA-CA, detail how we have adapted e-Delphi web application to support usability and utility evaluation of the PA-CA, and present the results of our evaluation. Results We report results from four sets of users. Each group provided structured individual and group assessments of the PA-CA as well as input on the kinds of users and applications for which it is best suited. Overall reactions to the PA-CA are quite positive. Participants did, however, provide a range of useful suggestions. Key suggestions focused on improving interaction functions, enhancing methods of temporal analysis, addressing data issues, and providing additional data displays and help functions. These suggestions were incorporated in each design and implementation iteration for the PA-CA and used to inform a set of web-atlas design principles. Conclusion For the Atlas, we find that a design that utilizes linked map, graph, and table views is understandable to and perceived to be useful by the target audience of cancer prevention and control professionals. However, it is clear that considerable variation in experience using maps and graphics exists and for those with less experience, integrated tutorials and help features are needed. In relation to our usability

  2. Maximum power flux of auroral kilometric radiation

    International Nuclear Information System (INIS)

    Benson, R.F.; Fainberg, J.

    1991-01-01

    The maximum auroral kilometric radiation (AKR) power flux observed by distant satellites has been increased by more than a factor of 10 from previously reported values. This increase has been achieved by a new data selection criterion and a new analysis of antenna spin modulated signals received by the radio astronomy instrument on ISEE 3. The method relies on selecting AKR events containing signals in the highest-frequency channel (1980, kHz), followed by a careful analysis that effectively increased the instrumental dynamic range by more than 20 dB by making use of the spacecraft antenna gain diagram during a spacecraft rotation. This analysis has allowed the separation of real signals from those created in the receiver by overloading. Many signals having the appearance of AKR harmonic signals were shown to be of spurious origin. During one event, however, real second harmonic AKR signals were detected even though the spacecraft was at a great distance (17 R E ) from Earth. During another event, when the spacecraft was at the orbital distance of the Moon and on the morning side of Earth, the power flux of fundamental AKR was greater than 3 x 10 -13 W m -2 Hz -1 at 360 kHz normalized to a radial distance r of 25 R E assuming the power falls off as r -2 . A comparison of these intense signal levels with the most intense source region values (obtained by ISIS 1 and Viking) suggests that multiple sources were observed by ISEE 3

  3. Usability Evaluation of Electronic Health Record System around Clinical Notes Usage-An Ethnographic Study.

    Science.gov (United States)

    Rizvi, Rubina F; Marquard, Jenna L; Hultman, Gretchen M; Adam, Terrence J; Harder, Kathleen A; Melton, Genevieve B

    2017-10-01

    Background A substantial gap exists between current Electronic Health Record (EHR) usability and potential optimal usability. One of the fundamental reasons for this discrepancy is poor incorporation of a User-Centered Design (UCD) approach during the Graphical User Interface (GUI) development process. Objective To evaluate usability strengths and weaknesses of two widely implemented EHR GUIs for critical clinical notes usage tasks. Methods Twelve Internal Medicine resident physicians interacting with one of the two EHR systems (System-1 at Location-A and System-2 at Location-B) were observed by two usability evaluators employing an ethnographic approach. User comments and observer findings were analyzed for two critical tasks: (1) clinical notes entry and (2) related information-seeking tasks. Data were analyzed from two standpoints: (1) usability references categorized by usability evaluators as positive, negative, or equivocal and (2) usability impact of each feature measured through a 7-point severity rating scale. Findings were also validated by user responses to a post observation questionnaire. Results For clinical notes entry, System-1 surpassed System-2 with more positive (26% vs. 12%) than negative (12% vs. 34%) usability references. Greatest impact features on EHR usability (severity score pertaining to each feature) for clinical notes entry were: autopopulation (6), screen options (5.5), communication (5), copy pasting (4.5), error prevention (4.5), edit ability (4), and dictation and transcription (3.5). Both systems performed equally well on information-seeking tasks and features with greatest impacts on EHR usability were navigation for notes (7) and others (e.g., looking for ancillary data; 5.5). Ethnographic observations were supported by follow-up questionnaire responses. Conclusion This study provides usability-specific insights to inform future, improved, EHR interface that is better aligned with UCD approach.

  4. Frequency standards

    CERN Document Server

    Riehle, Fritz

    2006-01-01

    Of all measurement units, frequency is the one that may be determined with the highest degree of accuracy. It equally allows precise measurements of other physical and technical quantities, whenever they can be measured in terms of frequency.This volume covers the central methods and techniques relevant for frequency standards developed in physics, electronics, quantum electronics, and statistics. After a review of the basic principles, the book looks at the realisation of commonly used components. It then continues with the description and characterisation of important frequency standards

  5. Transforming data into usable knowledge: the CIRC experience

    Science.gov (United States)

    Mote, P.; Lach, D.; Hartmann, H.; Abatzoglou, J. T.; Stevenson, J.

    2017-12-01

    NOAA's northwest RISA, the Climate Impacts Research Consortium, emphasizes the transformation of data into usable knowledge. This effort involves physical scientists (e.g., Abatzoglou) building web-based tools with climate and hydrologic data and model output, a team performing data mining to link crop loss claims to droughts, social scientists (eg., Lach, Hartmann) evaluating the effectiveness of such tools at communicating with end users, and two-way engagement with a wide variety of audiences who are interested in using and improving the tools. Unusual in this effort is the seamless integration across timescales past, present, and future; data mining; and the level of effort in evaluating the tools. We provide examples of agriculturally relevant climate variables (e.g. growing degree days, day of first fall freeze) and describe the iterative process of incorporating user feedback.

  6. Usability and Applicability of Microfluidic Cell Culture Systems

    DEFF Research Database (Denmark)

    Hemmingsen, Mette

    possibilities for, for example, precise control of the chemical environment, 3D cultures, controlled co-culture of different cell types or automated, individual control of up to 96 cell culture chambers in one integrated system. Despite the great new opportunities to perform novel experimental designs......Microfluidic cell culture has been a research area with great attention the last decade due to its potential to mimic the in vivo cellular environment more closely compared to what is possible by conventional cell culture methods. Many exciting and complex devices have been presented providing......, these devices still lack general implementation into biological research laboratories. In this project, the usability and applicability of microfluidic cell culture systems have been investigated. The tested systems display good properties regarding optics and compatibility with standard laboratory equipment...

  7. Usability of Security Management:Defining the Permissions of Guests

    Science.gov (United States)

    Johnson, Matthew; Stajano, Frank

    Within the scenario of a Smart Home, we discuss the issues involved in allowing limited interaction with the environment for unidentified principals, or guests. The challenges include identifying and authenticating guests on one hand and delegating authorization to them on the other. While the technical mechanisms for doing so in generic distributed systems have been around for decades, existing solutions are in general not applicable to the smart home because they are too complex to manage. We focus on providing both security and usability; we therefore seek simple and easy to understand approaches that can be used by a normal computer-illiterate home owner, not just by a trained system administrator. This position paper describes ongoing research and does not claim to have all the answers.

  8. An object-oriented mobile health system with usability features.

    Science.gov (United States)

    Escarfullet, Krystle; Moore, Cantera; Tucker, Shari; Wei, June

    2012-01-01

    Mobile health (m-health) comprises the concept of utilising mobile devices to carry out the task of viewing electronic medical records, reserving medical appointments with a patient's medical provider and electronically refilling prescriptions. This paper aims at developing a m-health system to improve usability from a user's perspective. Specifically, it first developed a m-health model by logically linking characteristics of the m-health system together based on information flows. Then, the system requirements were collected by using a developed questionnaire. These requirements were structured and further in-depth analysis was conducted by using an object-oriented approach based on unified modelling language, such as use-case, sequence and analysis class diagrams. This research will be beneficial to decision makers and developers in the mobile healthcare industry.

  9. Measurement of the Clinical Usability of a Configurable EHR

    DEFF Research Database (Denmark)

    Møller-Jensen, John; Lund Pedersen, Ivan; Simonsen, Jesper

    2006-01-01

    during a series of workshops with the clinicians after which the XML configuration files were written and deployed. In parallel with this, the participants from the University identified, prioritised and further specified a number of effects related to the clinical practice to be measured. The effects......The objective of the project was to measure the clinical usability of an EHR configured by use of participatory design with clinicians from a neurological stroke unit in order to get input to the County’s future strategy for incremental implementation of EHR. The content of the EHR was defined...... requested by the clinicians focused on improving their overview and assessment of patients as well as on more efficient coordination in three specific and highly cooperative situations, viz. nursing handover, ward round and patient conference. All three situations were measured before (using paper...

  10. Installation of the MAXIMUM microscope at the ALS

    International Nuclear Information System (INIS)

    Ng, W.; Perera, R.C.C.; Underwood, J.H.; Singh, S.; Solak, H.; Cerrina, F.

    1995-10-01

    The MAXIMUM scanning x-ray microscope, developed at the Synchrotron Radiation Center (SRC) at the University of Wisconsin, Madison was implemented on the Advanced Light Source in August of 1995. The microscope's initial operation at SRC successfully demonstrated the use of multilayer coated Schwarzschild objective for focusing 130 eV x-rays to a spot size of better than 0.1 micron with an electron energy resolution of 250meV. The performance of the microscope was severely limited, because of the relatively low brightness of SRC, which limits the available flux at the focus of the microscope. The high brightness of the ALS is expected to increase the usable flux at the sample by a factor of 1,000. The authors will report on the installation of the microscope on bending magnet beamline 6.3.2 at the ALS and the initial measurement of optical performance on the new source, and preliminary experiments with surface chemistry of HF etched Si will be described

  11. Usability evaluation of complex systems. A literature review

    International Nuclear Information System (INIS)

    Norros, L.; Savioja, P.

    2004-04-01

    In this literature study the task of usability evaluation is approached through recent publications and known practises. The scope of the reviewed literature and the overall problematic of evaluating complex systems are first defined. Then existing evaluation methods and tools and a set of design guidelines and standards is introduced. In there view the distinction between the evaluation of the design process and evaluation of the outcome of the design process is made. Also the existing criteria for usability is provided. These criteria can be used as measures in the evaluation procedures described in the previous chapter. Then, the problem of validity in the evaluation and validation procedures of complex cognitive systems is shortly discusses. The final chapter covers the conclusions of the literature review. There is a need for deepening the relationship between usage and design. Usage must be the driver also in the design of process technology, plant's safety, and instrumentation and control as well as that of the design of man-machine interface. The collaborative activity is called activity-oriented design. In order to enable activity-oriented design we need to create design methods that drive the design activity into this direction. Criteria for evaluating what is good design are not available in present standards. Criteria for good tools and practices must consider human in a favourable role in the various tasks of operating an industrial plant as opposed to the view of human as a source of error. This is the way to create an optimal system, which takes advantage of the unique capabilities of both the human operators and the automation systems. (orig.)

  12. The effect of sampling rate and anti-aliasing filters on high-frequency response spectra

    Science.gov (United States)

    Boore, David M.; Goulet, Christine

    2013-01-01

    The most commonly used intensity measure in ground-motion prediction equations is the pseudo-absolute response spectral acceleration (PSA), for response periods from 0.01 to 10 s (or frequencies from 0.1 to 100 Hz). PSAs are often derived from recorded ground motions, and these motions are usually filtered to remove high and low frequencies before the PSAs are computed. In this article we are only concerned with the removal of high frequencies. In modern digital recordings, this filtering corresponds at least to an anti-aliasing filter applied before conversion to digital values. Additional high-cut filtering is sometimes applied both to digital and to analog records to reduce high-frequency noise. Potential errors on the short-period (high-frequency) response spectral values are expected if the true ground motion has significant energy at frequencies above that of the anti-aliasing filter. This is especially important for areas where the instrumental sample rate and the associated anti-aliasing filter corner frequency (above which significant energy in the time series is removed) are low relative to the frequencies contained in the true ground motions. A ground-motion simulation study was conducted to investigate these effects and to develop guidance for defining the usable bandwidth for high-frequency PSA. The primary conclusion is that if the ratio of the maximum Fourier acceleration spectrum (FAS) to the FAS at a frequency fsaa corresponding to the start of the anti-aliasing filter is more than about 10, then PSA for frequencies above fsaa should be little affected by the recording process, because the ground-motion frequencies that control the response spectra will be less than fsaa . A second topic of this article concerns the resampling of the digital acceleration time series to a higher sample rate often used in the computation of short-period PSA. We confirm previous findings that sinc-function interpolation is preferred to the standard practice of using

  13. Sump water usability analysis following LB LOCA of CANDU 6 reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jang, M.S. [Nuclear Engineering Service & Solution, Daejeon (Korea, Republic of); Kim, S.M. [Korea Hydro and Nuclear Power Co. Ltd., Daejeon (Korea, Republic of); Moon, B.J.; Kim, S.R. [Nuclear Engineering Service & Solution, Daejeon (Korea, Republic of)

    2014-07-01

    This paper focused on the analysis of sump water usability as a source for low pressure emergency core cooling injection in CANDU 6 for large break loss of coolant accident, using GOTHIC-IST code. For a long term cooling, the operation of low pressure recirculation using an emergency core cooling pump is required. To operate an emergency core cooling pump, the net positive suction head of the pump should be satisfied. The maximum permissible temperature of sump water to meet the net positive suction head of an emergency core cooling pump is 87.73{sup o}C. In this study, the temperature and the level of sump water were monitored for the large break loss of coolant accident with malfunction of spray system and local air coolers. For all considered accident cases, the temperature of containment basement water was analyzed to be lower than 87.73{sup o}C and it was possible to operate the low pressure recirculation using an emergency core cooling pump for the most restricted scenario. (author)

  14. Two-dimensional maximum entropy image restoration

    International Nuclear Information System (INIS)

    Brolley, J.E.; Lazarus, R.B.; Suydam, B.R.; Trussell, H.J.

    1977-07-01

    An optical check problem was constructed to test P LOG P maximum entropy restoration of an extremely distorted image. Useful recovery of the original image was obtained. Comparison with maximum a posteriori restoration is made. 7 figures

  15. Frequency Synthesiser

    NARCIS (Netherlands)

    Drago, Salvatore; Sebastiano, Fabio; Leenaerts, Dominicus M.W.; Breems, Lucien J.; Nauta, Bram

    2016-01-01

    A low power frequency synthesiser circuit (30) for a radio transceiver, the synthesiser circuit comprising: a digital controlled oscillator configured to generate an output signal having a frequency controlled by an input digital control word (DCW); a feedback loop connected between an output and an

  16. Frequency synthesiser

    NARCIS (Netherlands)

    Drago, S.; Sebastiano, Fabio; Leenaerts, Dominicus Martinus Wilhelmus; Breems, Lucien Johannes; Nauta, Bram

    2010-01-01

    A low power frequency synthesiser circuit (30) for a radio transceiver, the synthesiser circuit comprising: a digital controlled oscillator configured to generate an output signal having a frequency controlled by an input digital control word (DCW); a feedback loop connected between an output and an

  17. Usability of Three Electroencephalogram Headsets for Brain-Computer Interfaces: A Within Subject Comparison

    NARCIS (Netherlands)

    Gamboa, H.; Nijboer, Femke; van de Laar, B.L.A.; Plácido da Silva, H.; Gilleade, K.; Gerritsen, Steven; Nijholt, Antinus; Bermúdez i Badia, S.; Poel, Mannes; Fairclough, S.

    Currently the field of brain–computer interfacing is increasingly focused on developing usable brain–computer interfaces (BCIs) to better ensure technology transfer and acceptance. Many studies have investigated the usability of BCI applications as a whole. Here we aim to investigate one specific

  18. Design and Usability of Digital Libraries: Case Studies in the Asia Pacific

    Science.gov (United States)

    Theng, Yin-Leng, Ed.; Foo, Schubert, Ed.

    2005-01-01

    This book showcases some of the best digital library practices from organizations in the Asia Pacific. Particular emphasis has been placed on the design, use and usability of digital libraries. Not only are digital libraries examined, but related technologies, the management of knowledge in digital libraries, and the associated usability and…

  19. Exploring the Role of Usability in the Software Process: A Study of Irish Software SMEs

    Science.gov (United States)

    O'Connor, Rory V.

    This paper explores the software processes and usability techniques used by Small and Medium Enterprises (SMEs) that develop web applications. The significance of this research is that it looks at development processes used by SMEs in order to assess to what degree usability is integrated into the process. This study seeks to gain an understanding into the level of awareness of usability within SMEs today and their commitment to usability in practice. The motivation for this research is to explore the current development processes used by SMEs in developing web applications and to understand how usability is represented in those processes. The background for this research is provided by the growth of the web application industry beyond informational web sites to more sophisticated applications delivering a broad range of functionality. This paper presents an analysis of the practices of several Irish SMEs that develop web applications through a series of case studies. With the focus on SMEs that develop web applications as Management Information Systems and not E-Commerce sites, informational sites, online communities or web portals. This study gathered data about the usability techniques practiced by these companies and their awareness of usability in the context of the software process in those SMEs. The contribution of this study is to further the understanding of the current role of usability within the software development processes of SMEs that develop web applications.

  20. 77 FR 8217 - Evaluating the Usability of Electronic Health Record (EHR) Systems

    Science.gov (United States)

    2012-02-14

    ... usability of health information technology (HIT) systems, EHRs in particular, and performance-oriented user... the usability of health information technology (HIT) systems. NIST research is designed to: (1... DEPARTMENT OF COMMERCE National Institute of Standards and Technology [Docket No. 120123059-2058...

  1. An Online Social Constructivist Course: Toward a Framework for Usability Evaluations

    Science.gov (United States)

    Phillips, Alana S.; Sheffield, Anneliese; Moore, Michelle; Robinson, Heather A.

    2016-01-01

    There is a need for a holistic usability evaluation framework that accommodates social constructivist online courses. Social knowledge construction may not be adequately evaluated using current frameworks. This qualitative research study examined the usability needs of a social constructivist online course. Data from an online course were analyzed…

  2. A usability evaluation of a SNOMED CT based compositional interface terminology for intensive care

    NARCIS (Netherlands)

    Bakhshi-Raiez, F.; de Keizer, N. F.; Cornet, R.; Dorrepaal, M.; Dongelmans, D.; Jaspers, M. W. M.

    2012-01-01

    Objective: To evaluate the usability of a large compositional interface terminology based on SNOMED CT and the terminology application for registration of the reasons for intensive care admission in a Patient Data Management System. Design: Observational study with user-based usability evaluations

  3. Towards an empirical method of usability testing of system parts : a methodological study

    NARCIS (Netherlands)

    Brinkman, W.P.; Haakma, R.; Bouwhuis, D.G.

    2007-01-01

    Current usability evaluation methods are essentially holistic in nature. However, engineers that apply a component-based software engineering approach might also be interested in understanding the usability of individual parts of an interactive system. This paper examines the efficiency dimension of

  4. A Proposal to Elicit Usability Requirements within a Model-Driven Development Environment

    NARCIS (Netherlands)

    Isela Ormeno, Y; Panach, I; Condori-Fernandez, O.N.; Pastor, O.

    2014-01-01

    Nowadays there are sound Model-Driven Development (MDD) methods that deal with functional requirements, but in general, usability is not considered from the early stages of the development. Analysts that work with MDD implement usability features manually once the code has been generated. This

  5. Usability Evaluation of a Video Conferencing System in a University’s Classroom

    DEFF Research Database (Denmark)

    Khalid, Md. Saifuddin; Hossan, Md. Iqbal

    2016-01-01

    -Time Communications (e.g. Google Hangout, Adobe Connect, Cisco WebEx, and appear.in), and dedicated (e.g. Polycom). There is a lack of empirical study on usability evaluation of the interactive systems in educational contexts. This study identifies usability errors and measures user satisfaction of a dedicated VCS...

  6. Using a fuzzy comprehensive evaluation method to determine product usability: A proposed theoretical framework.

    Science.gov (United States)

    Zhou, Ronggang; Chan, Alan H S

    2017-01-01

    In order to compare existing usability data to ideal goals or to that for other products, usability practitioners have tried to develop a framework for deriving an integrated metric. However, most current usability methods with this aim rely heavily on human judgment about the various attributes of a product, but often fail to take into account of the inherent uncertainties in these judgments in the evaluation process. This paper presents a universal method of usability evaluation by combining the analytic hierarchical process (AHP) and the fuzzy evaluation method. By integrating multiple sources of uncertain information during product usability evaluation, the method proposed here aims to derive an index that is structured hierarchically in terms of the three usability components of effectiveness, efficiency, and user satisfaction of a product. With consideration of the theoretical basis of fuzzy evaluation, a two-layer comprehensive evaluation index was first constructed. After the membership functions were determined by an expert panel, the evaluation appraisals were computed by using the fuzzy comprehensive evaluation technique model to characterize fuzzy human judgments. Then with the use of AHP, the weights of usability components were elicited from these experts. Compared to traditional usability evaluation methods, the major strength of the fuzzy method is that it captures the fuzziness and uncertainties in human judgments and provides an integrated framework that combines the vague judgments from multiple stages of a product evaluation process.

  7. Usability Assessment of E-Café Operational Management Simulation Game

    Science.gov (United States)

    Chang, Chiung-sui; Huang, Ya-Ping

    2013-01-01

    To ensure the quality of digital simulation game, we utilized the usability evaluation heuristic in the design and development processes of e-café operational management game-based learning material for students. The application of usability evaluations during this study is described. Additionally, participant selection, data collection and…

  8. The Focus of Current HCI Research in Usability Evaluation and Feedback

    DEFF Research Database (Denmark)

    Høegh, Rune Thaarup

    2007-01-01

    This paper presents the findings from a systematic literature study of the research on usability evaluation and feedback. The literature study covers the papers published from five key human-computer interaction journals for a period of four years, and depicts the most current research within...... the field with regard to usability evaluation and feedback....

  9. A Usability Study of Users' Perceptions toward a Multimedia Computer-Assisted Learning Tool for Neuroanatomy

    Science.gov (United States)

    Gould, Douglas J.; Terrell, Mark A.; Fleming, Jo

    2008-01-01

    This usability study evaluated users' perceptions of a multimedia prototype for a new e-learning tool: Anatomy of the Central Nervous System: A Multimedia Course. Usability testing is a collection of formative evaluation methods that inform the developmental design of e-learning tools to maximize user acceptance, satisfaction, and adoption.…

  10. An extended protocol for usability validation of medical devices : Research design and reference model

    NARCIS (Netherlands)

    Schmettow, M.; Schnittker, R.; Schraagen, J.M.

    2017-01-01

    This paper proposes and demonstrates an extended protocol for usability validation testing of medical devices. A review of currently used methods for the usability evaluation of medical devices revealed two main shortcomings. Firstly, the lack of methods to closely trace the interaction sequences

  11. Low-Cost Rapid Usability Testing: Its Application in Both Product Development and System Implementation.

    Science.gov (United States)

    Kushniruk, Andre; Borycki, Elizabeth

    2017-01-01

    In recent years there has been considerable discussion around the need for certification and regulation of healthcare information technology (IT). In particular, the usability of the products being developed needs to be evaluated. This has included the application of standards designed to ensure the process of system development is user-centered and takes usability into consideration while a product is being developed. In addition to this, in healthcare, organizations in the United States and Europe have also addressed the need and requirement for product certification. However, despite these efforts there are continued reports of unusable and unsafe implementations. In this paper we discuss the need to not only include (and require) usability testing in the one-time development process of health IT products (such as EHRs), but we also argue for the need to additionally develop specific usability standards and requirements for usability testing during the implementation of vendor products (i.e. post product development) in healthcare settings. It is further argued that health IT products that may have been certified regarding their development process will still require application of usability testing in the process of implementing them in real hospital settings in order to ensure usability and safety. This is needed in order to ensure that the final result of both product development and implementation processes take into account and apply the latest usability principles and methods.

  12. Methods uncovering usability issues in medication-related alerting functions: results from a systematic review.

    Science.gov (United States)

    Marcilly, Romaric; Vasseur, Francis; Ammenwerth, Elske; Beuscart-Zephir, Marie-Catherine

    2014-01-01

    This paper aims at listing the methods used to evaluate the usability of medication-related alerting functions and at knowing what type of usability issues those methods allow to detect. A sub-analysis of data from this systematic review has been performed. Methods applied in the included papers were collected. Then, included papers were sorted in four types of evaluation: "expert evaluation", "user- testing/simulation", "on site observation" and "impact studies". The types of usability issues (usability flaws, usage problems and negative outcomes) uncovered by those evaluations were analyzed. Results show that a large set of methods are used. The largest proportion of papers uses "on site observation" evaluation. This is the only evaluation type for which every kind of usability flaws, usage problems and outcomes are detected. It is somehow surprising that, in a usability systematic review, most of the papers included use a method that is not often presented as a usability method. Results are discussed about the opportunity to provide usability information collected after the implementation of the technology during their design process, i.e. before their implementation.

  13. The significance of a usability evaluation of an emerging laboratory order entry system

    NARCIS (Netherlands)

    Peute, Linda W. P.; Jaspers, Monique W. M.

    2007-01-01

    OBJECTIVES: To assess the usability of an emerging POE system, OM/Lab, for the computer-supported ordering of laboratory tests. We were more specifically interested in the relation of the usability problems detected in the user testing sessions with the order behaviour in terms of efficiency and

  14. Usability Testing for Developing Effective Interactive Multimedia Software: Concepts, Dimensions, and Procedures

    Directory of Open Access Journals (Sweden)

    Sung Heum Lee

    1999-04-01

    Full Text Available Usability testing is a dynamic process that can be used throughout the process of developing interactive multimedia software. The purpose of usability testing is to find problems and make recommendations to improve the utility of a product during its design and development. For developing effective interactive multimedia software, dimensions of usability testing were classified into the general categories of: learnability; performance effectiveness; flexibility; error tolerance and system integrity; and user satisfaction. In the process of usability testing, evaluation experts consider the nature of users and tasks, tradeoffs supported by the iterative design paradigm, and real world constraints to effectively evaluate and improve interactive multimedia software. Different methods address different purposes and involve a combination of user and usability testing, however, usability practitioners follow the seven general procedures of usability testing for effective multimedia development. As the knowledge about usability testing grows, evaluation experts will be able to choose more effective and efficient methods and techniques that are appropriate to their goals.

  15. Usability Evaluation of An Electronic Medication Administration Record (eMAR) Application

    Science.gov (United States)

    Guo, J.; Iribarren, S.; Kapsandoy, S.; Perri, S.; Staggers, N.

    2011-01-01

    Background Electronic medication administration records (eMARs) have been widely used in recent years. However, formal usability evaluations are not yet available for these vendor applications, especially from the perspective of nurses, the largest group of eMAR users. Objective To conduct a formal usability evaluation of an implemented eMAR. Methods Four evaluators examined a commercial vendor eMAR using heuristic evaluation techniques. The evaluators defined seven tasks typical of eMAR use and independently evaluated the application. Consensus techniques were used to obtain 100% agreement of identified usability problems and severity ratings. Findings were reviewed with 5 clinical staff nurses and the Director of Clinical Informatics who verified findings with a small group of clinical nurses. Results Evaluators found 60 usability problems categorized into 233 heuristic violations. Match, Error, and Visibility heuristics were the most frequently violated. Administer Medication and Order and Modify Medications tasks had the highest number of heuristic violations and usability problems rated as major or catastrophic. Conclusion The high number of usability problems could impact the effectiveness, efficiency and satisfaction of nurses’ medication administration activities and may include concerns about patient safety. Usability is a joint responsibility between sites and vendors. We offer a call to action for usability evaluations at all sites and eMAR application redesign as necessary to improve the user experience and promote patient safety. PMID:23616871

  16. Testing the usability of a personalized system: comparing the use of interviews, questionnaires and thinking -aloud

    NARCIS (Netherlands)

    van Velsen, Lex Stefan; van der Geest, Thea; Klaassen, R.F.

    2007-01-01

    Personalized systems present each user with tailored content or output. Testing the usability of such a system must take some specific usability issues and the suitability of the personalized output into account. In this study, we evaluated a personalized search engine to compare the use of

  17. Investigation on maximum transition temperature of phonon mediated superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Fusui, L; Yi, S; Yinlong, S [Physics Department, Beijing University (CN)

    1989-05-01

    Three model effective phonon spectra are proposed to get plots of {ital T}{sub {ital c}}-{omega} adn {lambda}-{omega}. It can be concluded that there is no maximum limit of {ital T}{sub {ital c}} in phonon mediated superconductivity for reasonable values of {lambda}. The importance of high frequency LO phonon is also emphasized. Some discussions on high {ital T}{sub {ital c}} are given.

  18. Investigating the effect of m-commerce design usability on customers' trust

    Science.gov (United States)

    Hussain, Azham Bin; Mahmood, Alaa Thamer; Naser, Raed Kamil

    2017-10-01

    User experience may vary from one user to another based on the design characteristics for processing a certain task. Our review of the literature revealed that there is a noticeable lack of studies on the effect of mobile or m-commerce design usability on customers' trust to perform certain activities. We investigated the effect of m-commerce design usability in terms of navigability, supportability, readability, creditability, and content relevant. A close-ended questionnaire was distributed to 20 customers who were asked to perform some tasks. The result showed that majority of the participants found m-commerce design usability to influence their trust of the app. The mentioned usability elements were found to positively influence customers' trust except for supportability. Our findings provide some insights to the m-commerce designers and developers and extend the current understanding about the potential of design usability in explaining users' usage behavior.

  19. Examining the Use of Usability Results in a Software Development Company

    DEFF Research Database (Denmark)

    Høegh, Rune Thaarup; Stage, Jan

    2004-01-01

    This paper presents the first results of a study on a usability evaluation for a Danish software development company. The use of the results from the usability evaluation is examined through interviews with two developers from the software company. It is through an interview with a project leader...... from the company found that the traditional usability report plays a very little role for the development team. Initial results suggest that textual feedback proves more valuable when accompanied with video and oral feedback.......This paper presents the first results of a study on a usability evaluation for a Danish software development company. The use of the results from the usability evaluation is examined through interviews with two developers from the software company. It is through an interview with a project leader...

  20. Implementing a collaborative virtual environment — specification for a usability metamodel

    Directory of Open Access Journals (Sweden)

    Maria L Villegas R

    2009-01-01

    Full Text Available This research presents the results of the first phase of a macro-project for constructing a collaborative virtual environment. It was aimed at selecting a graphical interface from five proposed for such environment, considering each one’s level of usability. Seve- ral standards of usability and user-centered design patterns were studied for specifying interface measurment criteria for speci- fying a usability metamodel; this defined the variables and rules to be taken into accout when measuring graphic user interface (GUI usability level for collaborative virtual environments. The use of metaphors when specifying graphic user interfaces is also briefly looked at as a source of new usability and satisfaction related to such interface use.

  1. Ergonomic adjustments on a website from the usability of functions: Can deficits impair functionalities?

    Directory of Open Access Journals (Sweden)

    Dalila Giovana Pagnoncelli Laperuta

    2017-09-01

    Full Text Available Current study assesses whether deficits and usability of ergonomics impair the functionality of a university website. The concepts of functionality, usability and ergonomics were foregrounded by contextualizing them within a university profile. Later, a satisfaction survey was proposed to users to measure the satisfaction in the use of the website and to map the problems in usability. In addition, an ergonomic inspection was performed on the site by applying Bastien and Scapin´s ergonomic criteria. After analyzing results by descriptive statistics and content analysis, the ergonomic and usability problems were detected, or rather, feedback deficits, minimum action (navigation, flexibility and experience impaired the excellence of website´s functionality, causing dissatisfaction or abandonment of the website by the users. After the analysis of the results, ergonomic adjustments were suggested for the website. They may be a help in new website projects or adjust products in which usability has not been incorporated to the development process.

  2. Usability of Low-Cost Android Data Collection System for Community-Based Participatory Research.

    Science.gov (United States)

    Salihu, Hamisu M; Salinas-Miranda, Abraham; Turner, DeAnne; King, Lindsey; Paothong, Arnut; Austin, Deborah; Berry, Estrellita Lo

    2016-01-01

    Android tablet computers can be valuable tools for data collection, but their usability has not been evaluated in community-based participatory research (CBPR). This article examines the usability of a low-cost bilingual touchscreen computerized survey system using Android tablets, piloted with a sample of 201 community residents in Tampa, Florida, from November 2013 to March 2014. Needs assessment questions were designed with the droidSURVEY software, and deployed using Android tablet computers. In addition, participants were asked questions about system usability. The mean system usability was 77.57 ± 17.66 (range, 0-100). The mean completion time for taking the 63 survey questions in the needs assessment was 23.11 ± 9.62 minutes. The survey completion rate was optimal (100%), with only 6.34% missingness per variable. We found no sociodemographic differences in usability scores. Our findings indicate that Android tablets could serve as useful tools in CBPR studies.

  3. The evaluator effect in usability studies: Problem detection and severity judgments

    DEFF Research Database (Denmark)

    Jacobsen, Niels Ebbe; Hertzum, Morten; John, Bonnie E.

    1998-01-01

    Usability studies are commonly used in industry and applied in research as a yardstick for other usability evaluation methods. Though usability studies have been studied extensively, one potential threat to their reliability has been left virtually untouched: the evaluator effect. In this study......, four evaluators individually analyzed four videotaped usability test sessions. Only 20% of the 93 detected problems were detected by all evaluators, and 46% were detected by only a single evaluator. From the total set of 93 problems the evaluators individually selected the ten problems they considered...... most severe. None of the selected severe problems appeared on all four evaluators’ top-10 lists, and 4 of the 11 problems that were considered severe by more than one evaluator were only detected by one or two evaluators. Thus, both detection of usability problems and selection of the most severe...

  4. Wireless application guidelines for usability design and evaluation for developing countries

    International Nuclear Information System (INIS)

    Khoja, S.A.; Ursani, A.A.; Ali, A.

    2009-01-01

    The aim of this paper is to provide guidelines for designing wireless applications. These guidelines are developed with the help of Human Computer Interaction based Usability Evaluation surveys and tests results. These guidelines will help in making wireless applications more usable and attractive for users and will help designers to plan effective interactive applications. The guidelines presented in the paper have been derived from the results of surveys, usability tests and SET (Summative Evaluation Tests) carried out over 200 people of Karachi, Pakistan, from different walks of life with different academic and professional backgrounds, making imperative suggestions not only to improve the usability of exciting features given in wireless and mobile products, but also provide suggestions to improve usability of basic components such as, text, navigation, interactivity, multimedia, control and behavior. (author)

  5. Receiver function estimated by maximum entropy deconvolution

    Institute of Scientific and Technical Information of China (English)

    吴庆举; 田小波; 张乃铃; 李卫平; 曾融生

    2003-01-01

    Maximum entropy deconvolution is presented to estimate receiver function, with the maximum entropy as the rule to determine auto-correlation and cross-correlation functions. The Toeplitz equation and Levinson algorithm are used to calculate the iterative formula of error-predicting filter, and receiver function is then estimated. During extrapolation, reflective coefficient is always less than 1, which keeps maximum entropy deconvolution stable. The maximum entropy of the data outside window increases the resolution of receiver function. Both synthetic and real seismograms show that maximum entropy deconvolution is an effective method to measure receiver function in time-domain.

  6. Systematic Review Protocol to Assess the Effectiveness of Usability Questionnaires in mHealth App Studies.

    Science.gov (United States)

    Zhou, Leming; Bao, Jie; Parmanto, Bambang

    2017-08-01

    Usability questionnaires have a wide use in mobile health (mHealth) app usability studies. However, no systematic review has been conducted for assessing the effectiveness of these questionnaires. This paper describes a protocol for conducting a systematic review of published questionnaire-based mHealth app usability studies. In this systematic review, we will select recently published (2008-2017) articles from peer-reviewed journals and conferences that describe mHealth app usability studies and implement at least one usability questionnaire. The search strategy will include terms such as "mobile app" and "usability." Multiple databases such as PubMed, CINAHL, IEEE Xplore, ACM Digital Library, and INSPEC will be searched. There will be 2 independent reviewers in charge of screening titles and abstracts as well as determining those articles that should be included for a full-text review. The third reviewer will act as a mediator between the other 2 reviewers. Moreover, a data extraction form will be created and used during the full article data analysis. Notably, the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines will be followed in reporting this protocol. A preliminary search produced 1271 articles, 40 of which are duplicate records. The inclusion-exclusion criteria are being strictly followed in performing the ongoing study selection. Usability questionnaires are an important tool in mHealth app usability studies. This review will summarize the usability questionnaires used in published research articles while assessing the efficacy of these questionnaires in determining the usability of mHealth apps. ©Leming Zhou, Jie Bao, Bambang Parmanto. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 01.08.2017.

  7. Investigation of the Usability of Computerized Critical Care Information Systems in Germany.

    Science.gov (United States)

    von Dincklage, Falk; Suchodolski, Klaudiusz; Lichtner, Gregor; Friesdorf, Wolfgang; Podtschaske, Beatrice; Ragaller, Maximilian

    2017-01-01

    The term "usability" describes how effectively, efficiently, and with what level of user satisfaction an information system can be used to accomplish specific goals. Computerized critical care information systems (CCISs) with high usability increase quality of care and staff satisfaction, while reducing medication errors. Conversely, systems lacking usability can interrupt clinical workflow, facilitate errors, and increase charting time. The aim of this study was to investigate and compare usability across CCIS currently used in Germany. In this study, German intensive care unit (ICU) nurses and physicians completed a specialized, previously validated, web-based questionnaire. The questionnaire assessed CCIS usability based on three rating models: an overall rating of the systems, a model rating technical usability, and a model rating task-specific usability. We analyzed results from 535 survey participants and compared eight different CCIS commonly used in Germany. Our results showed that usability strongly differs across the compared systems. The system ICUData had the best overall rating and technical usability, followed by the platforms ICM and MetaVision. The same three systems performed best in the rating of task-specific usability without significant differences between each other. Across all systems, overall ratings were more dependent on ease-of-use aspects than on aspects of utility/functionality, and the general scope of the functions offered was rated better than how well the functions are realized. Our results suggest that manufacturers should shift some of their effort away from the development of new features and focus more on improving the ease-of-use and quality of existing features.

  8. A usability evaluation of a SNOMED CT based compositional interface terminology for intensive care.

    Science.gov (United States)

    Bakhshi-Raiez, F; de Keizer, N F; Cornet, R; Dorrepaal, M; Dongelmans, D; Jaspers, M W M

    2012-05-01

    To evaluate the usability of a large compositional interface terminology based on SNOMED CT and the terminology application for registration of the reasons for intensive care admission in a Patient Data Management System. Observational study with user-based usability evaluations before and 3 months after the system was implemented and routinely used. Usability was defined by five aspects: effectiveness, efficiency, learnability, overall user satisfaction, and experienced usability problems. Qualitative (the Think-Aloud user testing method) and quantitative (the System Usability Scale questionnaire and Time-on-Task analyses) methods were used to examine these usability aspects. The results of the evaluation study revealed that the usability of the interface terminology fell short (SUS scores before and after implementation of 47.2 out of 100 and 37.5 respectively out of 100). The qualitative measurements revealed a high number (n=35) of distinct usability problems, leading to ineffective and inefficient registration of reasons for admission. The effectiveness and efficiency of the system did not change over time. About 14% (n=5) of the revealed usability problems were related to the terminology content based on SNOMED CT, while the remaining 86% (n=30) was related to the terminology application. The problems related to the terminology content were more severe than the problems related to the terminology application. This study provides a detailed insight into how clinicians interact with a controlled compositional terminology through a terminology application. The extensiveness, complexity of the hierarchy, and the language usage of an interface terminology are defining for its usability. Carefully crafted domain-specific subsets and a well-designed terminology application are needed to facilitate the use of a complex compositional interface terminology based on SNOMED CT. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  9. A comparison of usability methods for testing interactive health technologies: methodological aspects and empirical evidence.

    Science.gov (United States)

    Jaspers, Monique W M

    2009-05-01

    Usability evaluation is now widely recognized as critical to the success of interactive health care applications. However, the broad range of usability inspection and testing methods available may make it difficult to decide on a usability assessment plan. To guide novices in the human-computer interaction field, we provide an overview of the methodological and empirical research available on the three usability inspection and testing methods most often used. We describe two 'expert-based' and one 'user-based' usability method: (1) the heuristic evaluation, (2) the cognitive walkthrough, and (3) the think aloud. All three usability evaluation methods are applied in laboratory settings. Heuristic evaluation is a relatively efficient usability evaluation method with a high benefit-cost ratio, but requires high skills and usability experience of the evaluators to produce reliable results. The cognitive walkthrough is a more structured approach than the heuristic evaluation with a stronger focus on the learnability of a computer application. Major drawbacks of the cognitive walkthrough are the required level of detail of task and user background descriptions for an adequate application of the latest version of the technique. The think aloud is a very direct method to gain deep insight in the problems end users encounter in interaction with a system but data analyses is extensive and requires a high level of expertise both in the cognitive ergonomics and in computer system application domain. Each of the three usability evaluation methods has shown its usefulness, has its own advantages and disadvantages; no single method has revealed any significant results indicating that it is singularly effective in all circumstances. A combination of different techniques that compliment one another should preferably be used as their collective application will be more powerful than applied in isolation. Innovative mobile and automated solutions to support end-user testing have

  10. Maximum Power from a Solar Panel

    Directory of Open Access Journals (Sweden)

    Michael Miller

    2010-01-01

    Full Text Available Solar energy has become a promising alternative to conventional fossil fuel sources. Solar panels are used to collect solar radiation and convert it into electricity. One of the techniques used to maximize the effectiveness of this energy alternative is to maximize the power output of the solar collector. In this project the maximum power is calculated by determining the voltage and the current of maximum power. These quantities are determined by finding the maximum value for the equation for power using differentiation. After the maximum values are found for each time of day, each individual quantity, voltage of maximum power, current of maximum power, and maximum power is plotted as a function of the time of day.

  11. [Benefits and usability of a pharmaceutical record in medical practice. A survey of hospital doctors and pharmacists (MATRIX study)].

    Science.gov (United States)

    Schuers, M; Timsit, M; Gillibert, A; Fred, A; Griffon, N; Bénichou, J; Darmoni, S J; Staccini, P

    2016-09-01

    To evaluate the impact of the pharmaceutical patient record use in emergency, geriatric and anaesthesia and intensive care departments, an experimentation was launched in 2013 in 55 hospitals. The purpose of the study was to assess the opinions of physicians and pharmacists about the benefits and usability of the patient pharmaceutical record. An e-mailed self-administered questionnaire was sent to all the pharmacists, anaesthesiologists, geriatricians and emergency physicians of the 55 hospitals involved in the patient pharmaceutical record experimentation. The questionnaire assessed the usability of the patient pharmaceutical record using the "System Usability Scale", as well as its use, its benefits and limitations perceived in clinical practice, and overall user satisfaction. Questionnaires were collected from November 2014 to January 2015. Ninety-six questionnaires were collected, from 47 hospitals, representing 86% of the hospitals involved in the experimentation. The patient pharmaceutical record was effectively operational in 36 hospitals. Data from 73 questionnaires filled by physicians and pharmacists with potential experience with the patient pharmaceutical record were used for evaluation. Forty-two respondents were pharmacists (57%) and 31 were physicians (43%), including 13 geriatricians, 11 emergency physicians and 7 anaesthesiologists. Patient pharmaceutical record overall usability score was 62.5 out of 100. It did not vary with the profession or seniority of the respondent. It was positively correlated with the frequency of use. More than half of respondents reported that they never or uncommonly used the patient pharmaceutical record. The length of access to data period was considered as insufficient. Main obstacles to more utilization of the patient pharmaceutical record were the lack of information about the dosage of dispensed drugs, the low number of patients in possession of their health card and the low number of patients with an activated

  12. Usability and feasibility of health IT interventions to enhance Self-Care for Lymphedema Symptom Management in breast cancer survivors

    Directory of Open Access Journals (Sweden)

    Mei R. Fu, PhD, RN, FAAN

    2016-09-01

    Conclusions: This usability study provided evidence on breast cancer survivor's acceptance and highly positive evaluation of TOLF's usability as well as feasibility of using technologically-driven delivery model to enhance self-care strategies for lymphedema symptom management.

  13. Radio Frequency Energy Harvesting Sources

    Directory of Open Access Journals (Sweden)

    Action NECHIBVUTE

    2017-12-01

    Full Text Available This radio frequency (RF energy harvesting is an emerging technology and research area that promises to produce energy to run low-power wireless devices. The great interest that has recently been paid to RF harvesting is predominantly driven by the great progress in both wireless communication systems and broadcasting technologies that have availed a lot of freely propagating ambient RF energy. The principle aim of an RF energy harvesting system is to convert the received ambient RF energy into usable DC power. This paper presents a state of the art concise review of RF energy harvesting sources for low power applications, and also discusses open research questions and future research directions on ambient RF energy harvesting.

  14. Bridging the Divide: Translating Landsat Research Into Usable Science

    Science.gov (United States)

    Rocchio, L. E.; Davis, A. L.

    2006-12-01

    Science has long served humankind. Breakthroughs in medicine have increased longevity and advances in technology have made modern-day conveniences possible. Yet, social benefits begotten by the environmental sciences, although critical for the survival of humanity, have not always been as widely recognized or used. To benefit today's rapidly growing population, the divides between environmental research, applied environmental science, and use of this information by decision makers must be bridged. Lessons about the translation from research to usable science can be learned from the four decades of Landsat history, and these lessons can serve as useful models for bridging the gaps between new technology, scientific research, and the use of that research and technology in real-world problem solving. In 1965, William Pecora, then-director of the U.S. Geological Survey, proposed the idea of a remote sensing satellite program to gather facts about natural resources of Earth. For the next seven years, an intense campaign showing the depth and diversity of satellite imagery applications was waged. This led to the 1972 launch of the first civilian land-observing satellite, Landsat 1. By 1975, successful application research based on Landsat 1 imagery prompted then-NASA Administrator Dr. James Fletcher to proclaim that if one space age development would save the world, it would be Landsat and its successor satellites. Thirty-four years of continual Landsat imaging and related-research has lead to the implementation of many socially beneficial applications, such as improved water management techniques, crop insurance fraud reduction, illicit crop inventories, natural disaster relief planning, continent-scale carbon estimates, and extensive cartographic advances. Despite these successes, the challenge of translating Landsat research into realized social benefits remains. Even in this geospatially-savvy era, the utility of Landsat largely escapes policymakers. Here, in an

  15. Health system guidance appraisal--concept evaluation and usability testing.

    Science.gov (United States)

    Ako-Arrey, Denis E; Brouwers, Melissa C; Lavis, John N; Giacomini, Mita K

    2016-01-05

    Health system guidance (HSG) provides recommendations aimed to address health system challenges. However, there is a paucity of methods to direct, appraise, and report HSG. Earlier research identified 30 candidate criteria (concepts) that can be used to evaluate the quality of HSG and guide development and reporting requirements. The objective of this paper was to describe two studies aimed at evaluating the importance of these 30 criteria, design a draft HSG appraisal tool, and test its usability. This study involved a two-step survey process. In step 1, respondents rated the 30 concepts for appropriateness to, relevance to, and priority for health system decisions and HSG. This led to a draft tool. In step 2, respondents reviewed HSG documents, appraised them using the tool, and answered a series of questions. Descriptive analyses were computed. Fifty participants were invited in step 1, and we had a response rate of 82 %. The mean response rates for each concept within each survey question were universally favorable. There was also an overall agreement about the need for a high-quality tool to systematically direct the development, appraisal, and reporting of HSG. Qualitative feedback and a consensus process by the team led to refinements to some of the concepts and the creation of a beta (draft) version of the HSG tool. In step 2, 35 participants were invited and we had a response rate of 74 %. Exploratory analyses showed that the quality of the HSGs reviewed varied as a function of the HSG item and the specific document assessed. A favorable consensus was reached with participants agreeing that the HSG items were easy to understand and easy to apply. Moreover, the overall agreement was high for the usability of the tool to systematically direct the development (85 %), appraisal (92 %), and reporting (81 %) of HSG. From this process, version 1.0 of the HSG appraisal tool was generated complete with 32 items (and their descriptions) and 4 domains. The final

  16. Narrow band interference cancelation in OFDM: Astructured maximum likelihood approach

    KAUST Repository

    Sohail, Muhammad Sadiq

    2012-06-01

    This paper presents a maximum likelihood (ML) approach to mitigate the effect of narrow band interference (NBI) in a zero padded orthogonal frequency division multiplexing (ZP-OFDM) system. The NBI is assumed to be time variant and asynchronous with the frequency grid of the ZP-OFDM system. The proposed structure based technique uses the fact that the NBI signal is sparse as compared to the ZP-OFDM signal in the frequency domain. The structure is also useful in reducing the computational complexity of the proposed method. The paper also presents a data aided approach for improved NBI estimation. The suitability of the proposed method is demonstrated through simulations. © 2012 IEEE.

  17. Determining the Number of Participants Needed for the Usability Evaluation of E-Learning Resources: A Monte Carlo Simulation

    Science.gov (United States)

    Davids, Mogamat Razeen; Harvey, Justin; Halperin, Mitchell L.; Chikte, Usuf M. E.

    2015-01-01

    The usability of computer interfaces has a major influence on learning. Optimising the usability of e-learning resources is therefore essential. However, this may be neglected because of time and monetary constraints. User testing is a common approach to usability evaluation and involves studying typical end-users interacting with the application…

  18. Improving the Usability of the User Interface for a Digital Textbook Platform for Elementary-School Students

    Science.gov (United States)

    Lim, Cheolil; Song, Hae-Deok; Lee, Yekyung

    2012-01-01

    Usability is critical to the development of a user-friendly digital textbook platform interface, yet thorough research on interface development based on usability principles is in short supply. This study addresses that need by looking at usability attributes and corresponding design elements from a learning perspective. The researchers used a…

  19. An empirical study on website usability elements and how they affect search engine optimisation

    Directory of Open Access Journals (Sweden)

    Eugene B. Visser

    2011-03-01

    Full Text Available The primary objective of this research project was to identify and investigate the website usability attributes which are in contradiction with search engine optimisation elements. The secondary objective was to determine if these usability attributes affect conversion. Although the literature review identifies the contradictions, experts disagree about their existence.An experiment was conducted, whereby the conversion and/or traffic ratio results of an existing control website were compared to a usability-designed version of the control website,namely the experimental website. All optimisation elements were ignored, thus implementing only usability. The results clearly show that inclusion of the usability attributes positively affect conversion,indicating that usability is a prerequisite for effective website design. Search engine optimisation is also a prerequisite for the very reason that if a website does not rank on the first page of the search engine result page for a given keyword, then that website might as well not exist. According to this empirical work, usability is in contradiction to search engine optimisation best practices. Therefore the two need to be weighed up in terms of importance towards search engines and visitors.

  20. A Usability Study of Users’ Perceptions Toward a Multimedia Computer-Assisted Learning Tool for Neuroanatomy

    Science.gov (United States)

    Gould, Douglas J.; Terrell, Mark A.; Fleming, Jo

    2015-01-01

    This usability study evaluated users’ perceptions of a multimedia prototype for a new e-learning tool: Anatomy of the Central Nervous System: A Multimedia Course. Usability testing is a collection of formative evaluation methods that inform the developmental design of e-learning tools to maximize user acceptance, satisfaction, and adoption. Sixty-two study participants piloted the prototype and completed a usability questionnaire designed to measure two usability properties: program need and program applicability. Statistical analyses were used to test the hypothesis that the multimedia prototype was well designed and highly usable, it was perceived as: 1) highly needed across a spectrum of educational contexts, 2) highly applicable in supporting the pedagogical processes of teaching and learning neuroanatomy, and 3) was highly usable by all types of users. Three independent variables represented user differences: level of expertise (faculty vs. student), age, and gender. Analysis of the results supports the research hypotheses that the prototype was designed well for different types of users in various educational contexts and for supporting the pedagogy of neuroanatomy. In addition, the results suggest that the multimedia program will be most useful as a neuroanatomy review tool for health-professions students preparing for licensing or board exams. This study demonstrates the importance of integrating quality properties of usability with principles of human learning during the instructional design process for multimedia products. PMID:19177405

  1. Comparison of two heuristic evaluation methods for evaluating the usability of health information systems.

    Science.gov (United States)

    Khajouei, Reza; Hajesmaeel Gohari, Sadrieh; Mirzaee, Moghaddameh

    2018-04-01

    In addition to following the usual Heuristic Evaluation (HE) method, the usability of health information systems can also be evaluated using a checklist. The objective of this study is to compare the performance of these two methods in identifying usability problems of health information systems. Eight evaluators independently evaluated different parts of a Medical Records Information System using two methods of HE (usual and with a checklist). The two methods were compared in terms of the number of problems identified, problem type, and the severity of identified problems. In all, 192 usability problems were identified by two methods in the Medical Records Information System. This was significantly higher than the number of usability problems identified by the checklist and usual method (148 and 92, respectively) (p information systems. The results demonstrated that the checklist method had significantly better performance in terms of the number of identified usability problems; however, the performance of the usual method for identifying problems of higher severity was significantly better. Although the checklist method can be more efficient for less experienced evaluators, wherever usability is critical, the checklist should be used with caution in usability evaluations. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Are three methods better than one? A comparative assessment of usability evaluation methods in an EHR.

    Science.gov (United States)

    Walji, Muhammad F; Kalenderian, Elsbeth; Piotrowski, Mark; Tran, Duong; Kookal, Krishna K; Tokede, Oluwabunmi; White, Joel M; Vaderhobli, Ram; Ramoni, Rachel; Stark, Paul C; Kimmes, Nicole S; Lagerweij, Maxim; Patel, Vimla L

    2014-05-01

    To comparatively evaluate the effectiveness of three different methods involving end-users for detecting usability problems in an EHR: user testing, semi-structured interviews and surveys. Data were collected at two major urban dental schools from faculty, residents and dental students to assess the usability of a dental EHR for developing a treatment plan. These included user testing (N=32), semi-structured interviews (N=36), and surveys (N=35). The three methods together identified a total of 187 usability violations: 54% via user testing, 28% via the semi-structured interview and 18% from the survey method, with modest overlap. These usability problems were classified into 24 problem themes in 3 broad categories. User testing covered the broadest range of themes (83%), followed by the interview (63%) and survey (29%) methods. Multiple evaluation methods provide a comprehensive approach to identifying EHR usability challenges and specific problems. The three methods were found to be complementary, and thus each can provide unique insights for software enhancement. Interview and survey methods were found not to be sufficient by themselves, but when used in conjunction with the user testing method, they provided a comprehensive evaluation of the EHR. We recommend using a multi-method approach when testing the usability of health information technology because it provides a more comprehensive picture of usability challenges. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  3. What makes a control system usable? An operational viewpoint

    International Nuclear Information System (INIS)

    Clay, M.

    1990-01-01

    This report discusses the generally accepted successes and shortcomings of the various computer and hardware-based control systems at the Los Alamos Meson Physics Facility (LAMPF) from an operator's standpoint. LAMPF currently utilizes three separate control rooms that, although critically co-dependent, use distinct operating methods. The first, the Injector Control Room, which is responsible for the operation of the three ion sources, the 750 keV transport lines and the 201.25 MHz portion of the linac, uses a predominantly hardware-based control system. The second, the LANSCE Control Room, which is responsible for the operation of the Los Alamos Neutron Scattering Center, uses a graphical touch-panel interface with single-application screens as its control system. The third, the LAMPF Central Control Room, which is responsible for the overall operation of LAMPF, primarily uses a text-oriented keyboard interface with multiple applications per screen. Though each system provides generally reliable human interfacing to the enormously complex and diverse machine known as LAMPF, the operational requirements of speed, usability, and reliability are increasingly necessitating the use of a standard control system that incorporates the positive aspects of all three control systems. (orig.)

  4. Optimizing the Usability of Brain-Computer Interfaces.

    Science.gov (United States)

    Zhang, Yin; Chase, Steve M

    2018-03-22

    Brain-computer interfaces are in the process of moving from the laboratory to the clinic. These devices act by reading neural activity and using it to directly control a device, such as a cursor on a computer screen. An open question in the field is how to map neural activity to device movement in order to achieve the most proficient control. This question is complicated by the fact that learning, especially the long-term skill learning that accompanies weeks of practice, can allow subjects to improve performance over time. Typical approaches to this problem attempt to maximize the biomimetic properties of the device in order to limit the need for extensive training. However, it is unclear if this approach would ultimately be superior to performance that might be achieved with a nonbiomimetic device once the subject has engaged in extended practice and learned how to use it. Here we approach this problem using ideas from optimal control theory. Under the assumption that the brain acts as an optimal controller, we present a formal definition of the usability of a device and show that the optimal postlearning mapping can be written as the solution of a constrained optimization problem. We then derive the optimal mappings for particular cases common to most brain-computer interfaces. Our results suggest that the common approach of creating biomimetic interfaces may not be optimal when learning is taken into account. More broadly, our method provides a blueprint for optimal device design in general control-theoretic contexts.

  5. The Effectiveness and Clinical Usability of a Handheld Information Appliance

    Directory of Open Access Journals (Sweden)

    Patricia A. Abbott

    2012-01-01

    Full Text Available Clinical environments are complex, stressful, and safety critical—heightening the demand for technological solutions that will help clinicians manage health information efficiently and safely. The industry has responded by creating numerous, increasingly compact and powerful health IT devices that fit in a pocket, hook to a belt, attach to eyeglasses, or wheel around on a cart. Untethering a provider from a physical “place” with compact, mobile technology while delivering the right information at the right time and at the right location are generally welcomed in clinical environments. These developments however, must be looked at ecumenically. The cognitive load of clinicians who are occupied with managing or operating several different devices during the process of a patient encounter is increased, and we know from decades of research that cognitive overload frequently leads to error. “Technology crowding,” enhanced by the plethora of mobile health IT, can actually become an additional millstone for busy clinicians. This study was designed to gain a deeper understanding of clinicians’ interactions with a mobile clinical computing appliance (Motion Computing C5 designed to consolidate numerous technological functions into an all-in-one device. Features of usability and comparisons to current methods of documentation and task performance were undertaken and results are described.

  6. Usability of a Wearable Camera System for Dementia Family Caregivers

    Directory of Open Access Journals (Sweden)

    Judith T. Matthews

    2015-01-01

    Full Text Available Health care providers typically rely on family caregivers (CG of persons with dementia (PWD to describe difficult behaviors manifested by their underlying disease. Although invaluable, such reports may be selective or biased during brief medical encounters. Our team explored the usability of a wearable camera system with 9 caregiving dyads (CGs: 3 males, 6 females, 67.00 ± 14.95 years; PWDs: 2 males, 7 females, 80.00 ± 3.81 years, MMSE 17.33 ± 8.86 who recorded 79 salient events over a combined total of 140 hours of data capture, from 3 to 7 days of wear per CG. Prior to using the system, CGs assessed its benefits to be worth the invasion of privacy; post-wear privacy concerns did not differ significantly. CGs rated the system easy to learn to use, although cumbersome and obtrusive. Few negative reactions by PWDs were reported or evident in resulting video. Our findings suggest that CGs can and will wear a camera system to reveal their daily caregiving challenges to health care providers.

  7. Usability Operations on Touch Mobile Devices for Users with Autism.

    Science.gov (United States)

    Quezada, Angeles; Juárez-Ramírez, Reyes; Jiménez, Samantha; Noriega, Alan Ramírez; Inzunza, Sergio; Garza, Arnulfo Alanis

    2017-10-14

    The Autistic Spectrum Disorder is a cognitive disorder that affects the cognitive and motor skills; due that, users cannot perform digital and fine motor tasks. It is necessary to create software applications that adapt to the abilities of these users. In recent years has been an increase in the research of the use of technology to support autistic users to develop their communication skills and to improve learning. However, the applications' usability for disable users is not assessed objectively as the existing models do not consider interaction operators for disable users. This article focuses on identifying the operations that can easily be performed by autistic users following the metrics of KML-GOMS, TLM and FLM. In addition, users of typical development were included in order to do a comparison between both types of users. The experiment was carried out using four applications designed for autistic users. Participants were subjects divided in two groups: level 1 and level 2 autistic users, and a group of users of typical development. During the experimentation, users performed a use case for each application; the time needed to perform each task was measured. Results show that the easiest operations for autistic users are K (Keystroke), D (Drag), Initial Act (I) and Tapping (T).

  8. Task analysis: How far are we from usable PRA input

    International Nuclear Information System (INIS)

    Gertman, D.I.; Blackman, H.S.; Hinton, M.F.

    1984-01-01

    This chapter reviews data collected at the Idaho National Engineering Laboratory for three DOE-owned reactors (the Advanced Test Reactor, the Power Burst Facility, and the Loss of Fluids Test Reactor) in order to identify usable Probabilistic Risk Assessment (PRA) input. Task analytic procedures involve the determination of manning and skill levels as a means of determining communication requirements, in assessing job performance aids, and in assessing the accuracy and completeness of emergency and maintenance procedures. The least understood aspect in PRA and plant reliability models is the human factor. A number of examples from the data base are discussed and offered as a means of providing more meaningful data than has been available to PRA analysts in the past. It is concluded that the plant hardware-procedures-personnel interfaces are essential to safe and efficient plant operations and that task analysis is a reasonably sound way of achieving a qualitative method for identifying those tasks most strongly associated with task difficulty, severity of consequence, and error probability

  9. Maximum permissible voltage of YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z. [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Hong, Z., E-mail: zhiyong.hong@sjtu.edu.cn [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Wang, D.; Zhou, H.; Shen, X.; Shen, C. [Qingpu Power Supply Company, State Grid Shanghai Municipal Electric Power Company, Shanghai (China)

    2014-06-15

    Highlights: • We examine three kinds of tapes’ maximum permissible voltage. • We examine the relationship between quenching duration and maximum permissible voltage. • Continuous I{sub c} degradations under repetitive quenching where tapes reaching maximum permissible voltage. • The relationship between maximum permissible voltage and resistance, temperature. - Abstract: Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (I{sub c}) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the I{sub c} degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

  10. Designing Telemedicine Systems for Geriatric Patients: A Review of the Usability Studies.

    Science.gov (United States)

    Narasimha, Shraddhaa; Madathil, Kapil Chalil; Agnisarman, Sruthy; Rogers, Hunter; Welch, Brandon; Ashok, Aparna; Nair, Aswathi; McElligott, James

    2017-06-01

    One area where telemedicine may prove to be highly effective is in providing medical care to the geriatric population, an age group predicted to account for 20% of the population in the near future. However, even though telemedicine has certain advantages, the usability of these systems with this population merits investigation. This article reviews the literature published from 2000 to 2016 with the goal of analyzing the characteristics of usability-related studies conducted using geriatric participants and the subsequent usability challenges identified. Articles were found using Web of Knowledge and PubMed citation indexing portals using the keywords (1) Telemedicine* AND Geriatrics* (2) Telemedicine* AND Usability* (3) Telemedicine* AND Usability* AND Older Adults*. A total of 297 articles were obtained from the initial search. After further detailed screening, 16 articles were selected for review based on the inclusion criteria. Of these, 60% of the studies focused on the overall usability of telemedicine systems; 6.25% focused on the usability of a telepresence robot; 12.5% compared a face-to-face medical consultation with the use of telemedicine systems, and 25% focused on the study of other aspects of telemedicine in addition to its usability. Findings reported in the studies included high patient satisfaction with telemedicine in 31.25%, whereas another 31.25% indicated a high acceptance of this method of medical consultation. Care coordination in 6.25% of the studies; confidence in telemedicine in 6.25%; trust, privacy, and reliability in 6.25%; and increased convenience when compared to personal visits in 18.75% were also reported. This review suggests limited research providing scientifically valid and reproducible usability evaluation at various stages of telemedicine system development. Telemedicine system designers need to consider the age-related issues in cognition, perception, and behavior of geriatric patients while designing telemedicine

  11. Usability in product development practice; an exploratory case study comparing four markets.

    Science.gov (United States)

    van Kuijk, Jasper; van Driel, Liesbeth; van Eijk, Daan

    2015-03-01

    This study explored how usability was dealt with in four product development organizations active in different sectors: high-end automotive, professional printers and copiers, office coffee makers and fast moving consumer goods. The primary differentiators of the selected cases were whether they were targeting businesses or consumers and the degree of product complexity. Interviews with 19 product development practitioners were conducted, focussing on three topics: 1) the product development process and the integration of user involvement, 2) multidisciplinary teamwork, and 3) organizational attitude towards usability. Based on the interviews, context descriptions of the companies were created and barriers and enablers for usability were identified. To verify the findings and to discuss remaining issues a feedback workshop was held in which the primary contact from each company participated. The results indicate that differences in product-market combination lead to differences in organizational attitude towards usability. The prioritization of usability in an organization seems to be influenced by the degree of product complexity (complex products are more prone to suffer from usability issues) and whether developers think that usability is a purchase consideration for their clients. The product-market combination a company targets also affects the methods for user-centred design that a company can apply and that are relevant. What methods for user-centred design are used also seems to be influenced by the attitude towards usability: if usability is considered more important, methods that require more resources can be applied. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  12. Frequency spirals

    International Nuclear Information System (INIS)

    Ottino-Löffler, Bertrand; Strogatz, Steven H.

    2016-01-01

    We study the dynamics of coupled phase oscillators on a two-dimensional Kuramoto lattice with periodic boundary conditions. For coupling strengths just below the transition to global phase-locking, we find localized spatiotemporal patterns that we call “frequency spirals.” These patterns cannot be seen under time averaging; they become visible only when we examine the spatial variation of the oscillators' instantaneous frequencies, where they manifest themselves as two-armed rotating spirals. In the more familiar phase representation, they appear as wobbly periodic patterns surrounding a phase vortex. Unlike the stationary phase vortices seen in magnetic spin systems, or the rotating spiral waves seen in reaction-diffusion systems, frequency spirals librate: the phases of the oscillators surrounding the central vortex move forward and then backward, executing a periodic motion with zero winding number. We construct the simplest frequency spiral and characterize its properties using analytical and numerical methods. Simulations show that frequency spirals in large lattices behave much like this simple prototype.

  13. Frequency spirals

    Energy Technology Data Exchange (ETDEWEB)

    Ottino-Löffler, Bertrand; Strogatz, Steven H., E-mail: strogatz@cornell.edu [Center for Applied Mathematics, Cornell University, Ithaca, New York 14853 (United States)

    2016-09-15

    We study the dynamics of coupled phase oscillators on a two-dimensional Kuramoto lattice with periodic boundary conditions. For coupling strengths just below the transition to global phase-locking, we find localized spatiotemporal patterns that we call “frequency spirals.” These patterns cannot be seen under time averaging; they become visible only when we examine the spatial variation of the oscillators' instantaneous frequencies, where they manifest themselves as two-armed rotating spirals. In the more familiar phase representation, they appear as wobbly periodic patterns surrounding a phase vortex. Unlike the stationary phase vortices seen in magnetic spin systems, or the rotating spiral waves seen in reaction-diffusion systems, frequency spirals librate: the phases of the oscillators surrounding the central vortex move forward and then backward, executing a periodic motion with zero winding number. We construct the simplest frequency spiral and characterize its properties using analytical and numerical methods. Simulations show that frequency spirals in large lattices behave much like this simple prototype.

  14. Beyond the Usability Lab Conducting Large-scale Online User Experience Studies

    CERN Document Server

    Albert, William; Tullis, Thomas

    2010-01-01

    Usability testing and user experience research typically take place in a controlled lab with small groups. While this type of testing is essential to user experience design, more companies are also looking to test large sample sizes to be able compare data according to specific user populations and see how their experiences differ across user groups. But few usability professionals have experience in setting up these studies, analyzing the data, and presenting it in effective ways.  Online usability testing offers the solution by allowing testers to elicit feedback simultaneously from 1,0

  15. Design of New-Generation Usable Forms of Topical Haemostatic Agents Containing Chitosan

    Directory of Open Access Journals (Sweden)

    Dorota Zielińska

    2017-12-01

    Full Text Available Designing usable forms of topical haemostatic agents is the most important activity during the design process, resulting in strengthened functional properties of the final medical devices. This study aimed to propose indications for a research programme based on risk management supporting the development of two usable forms of a topical haemostatic agent: chitosan/alginate lyophilized foam and chitosan/alginate impregnated gauze. Both of the usable forms of the topical haemostatic agent, being the main part of the modified combat gauze, were fabricated using the chitosan/alginate complex. Risk analysis is helpful in developing an appropriate research programme, significantly reducing the risk to an acceptable level.

  16. Finding online health-related information: usability issues of health portals.

    Science.gov (United States)

    Gurel Koybasi, Nergis A; Cagiltay, Kursat

    2012-01-01

    As Internet and computers become widespread, health portals offering online health-related information become more popular. The most important point for health portals is presenting reliable and valid information. Besides, portal needs to be usable to be able to serve information to users effectively. This study aims to determine usability issues emerging when health-related information is searched on a health portal. User-based usability tests are conducted and eye movement analyses are used in addition to traditional performance measures. Results revealed that users prefer systematic, simple and consistent designs offering interactive tools. Moreover, content and partitions needs to be shaped according to the medical knowledge of target users.

  17. Assessment of the usability of a digital learning technology prototype for monitoring intracranial pressure

    Directory of Open Access Journals (Sweden)

    Lilian Regina de Carvalho

    Full Text Available ABSTRACT Objective: to assess the usability of a digital learning technology prototype as a new method for minimally invasive monitoring of intracranial pressure. Method: descriptive study using a quantitative approach on assessing the usability of a prototype based on Nielsen's ten heuristics. Four experts in the area of Human-Computer interaction participated in the study. Results: the evaluation delivered eight violated heuristics and 31 usability problems in the 32 screens of the prototype. Conclusion: the suggestions of the evaluators were critical for developing an intuitive, user-friendly interface and will be included in the final version of the digital learning technology.

  18. Usability Assessment of the Missouri Cancer Registry’s Published Interactive Mapping Reports: Round One

    Science.gov (United States)

    Jackson-Thompson, Jeannette; Schmaltz, Chester Lee

    2017-01-01

    Background  Many users of spatial data have difficulty interpreting information in health-related spatial reports. The Missouri Cancer Registry and Research Center (MCR-ARC) has produced interactive reports for several years. These reports have never been tested for usability. Objective  The aims of this study were to: (1) conduct a multi-approach usability testing study to understand ease of use (user friendliness) and user satisfaction; and (2) evaluate the usability of MCR-ARC’s published InstantAtlas reports. Methods   An institutional review board (IRB) approved mixed methodology usability testing study using a convenience sample of health professionals. A recruiting email was sent to faculty in the Master of Public Health program and to faculty and staff in the Department of Health Management and Informatics at the University of Missouri-Columbia. The study included 7 participants. The test included a pretest questionnaire, a multi-task usability test, and the System Usability Scale (SUS). Also, the researchers collected participants’ comments about the tested maps immediately after every trial. Software was used to record the computer screen during the trial and the participants’ spoken comments. Several performance and usability metrics were measured to evaluate the usability of MCR-ARC’s published mapping reports. Results Of the 10 assigned tasks, 6 reached a 100% completion success rate, and this outcome was relative to the complexity of the tasks. The simple tasks were handled more efficiently than the complicated tasks. The SUS score ranged between 20-100 points, with an average of 62.7 points and a median of 50.5 points. The tested maps’ effectiveness outcomes were better than the efficiency and satisfaction outcomes. There was a statistically significant relationship between the subjects’ performance on the study test and the users’ previous experience with geographic information system (GIS) tools (P=.03). There were no

  19. Evaluating the usability of a virtual reality-based Android application in managing the pain experience of wheelchair users.

    Science.gov (United States)

    Spyridonis, Fotios; Gronli, Tor-Morten; Hansen, Jarle; Ghinea, Gheorghita

    2012-01-01

    Pain constitutes an important medical concern that can have severe implications to a wheelchair user's quality of life. Results from studies indicate that pain is a common problem in this group of individuals, having a reported frequency of always (12%) and everyday (33%). This incidence signifies the need for more applicable and effective pain management clinical tools. As a result, in this paper we present an Android application (PainDroid) that has been enhanced with Virtual Reality (VR) technology for the purpose of improving the management of pain. Our evaluation with a group of wheelchair users revealed that PainDroid demonstrated high usability among this population, and is foreseen that it can make an important contribution in research on the assessment and management of pain.

  20. Acceptance and usability of a home-based monitoring tool of health indicators in children of people with dementia: a Proof of Principle (POP study

    Directory of Open Access Journals (Sweden)

    Boessen AB

    2017-08-01

    Full Text Available April BCG Boessen,1 Joan Vermeulen,2 Luc P de Witte3 1Research Centre for Technology in Care, Faculty of Health, Zuyd University of Applied Sciences, Heerlen, the Netherlands; 2Lunet zorg, Eindhoven, the Netherlands; 3The Innovation Centre, The University of Sheffield, Sheffield, UK Background: Large-scale cohort studies are needed to confirm the relation between dementia and its possible risk factors. The inclusion of people with dementia in research is a challenge, however, children of people with dementia are at risk and are highly motivated to participate in dementia research. For technologies to support home-based data collection during large-scale studies, participants should be able and willing to use technology for a longer period of time. Objective: This study investigated acceptance and usability of iVitality, a research platform for home-based monitoring of dementia health indicators, in 151 children of people with dementia and investigated which frequency of measurements is acceptable for them. Methods: Participants were randomized to fortnightly or monthly measurements. At baseline and after 3 months, participants completed an online questionnaire regarding the acceptance (Technology Acceptance Model; 38 items and usability (Post-Study System Usability Questionnaire; 24 items of iVitality. Items were rated from 1 (I totally disagree to 7 (I totally agree. Participants were also invited to take part in an online focus group (OFG after 3 months of follow-up. Descriptive statistics and both two-sample/independent and paired t-tests were used to analyze the online questionnaires and a directed content analysis was used to analyze the OFGs. Results: Children of people with dementia accept iVitality after long-term use and evaluate iVitality as a user-friendly, useful, and trusted technology, despite some suggestions for improvement. Overall, mean scores on acceptance and usability were higher than 5 (I somewhat agree, although the

  1. Revealing the Maximum Strength in Nanotwinned Copper

    DEFF Research Database (Denmark)

    Lu, L.; Chen, X.; Huang, Xiaoxu

    2009-01-01

    boundary–related processes. We investigated the maximum strength of nanotwinned copper samples with different twin thicknesses. We found that the strength increases with decreasing twin thickness, reaching a maximum at 15 nanometers, followed by a softening at smaller values that is accompanied by enhanced...

  2. Modelling maximum canopy conductance and transpiration in ...

    African Journals Online (AJOL)

    There is much current interest in predicting the maximum amount of water that can be transpired by Eucalyptus trees. It is possible that industrial waste water may be applied as irrigation water to eucalypts and it is important to predict the maximum transpiration rates of these plantations in an attempt to dispose of this ...

  3. Maximum nondiffracting propagation distance of aperture-truncated Airy beams

    Science.gov (United States)

    Chu, Xingchun; Zhao, Shanghong; Fang, Yingwu

    2018-05-01

    Airy beams have called attention of many researchers due to their non-diffracting, self-healing and transverse accelerating properties. A key issue in research of Airy beams and its applications is how to evaluate their nondiffracting propagation distance. In this paper, the critical transverse extent of physically realizable Airy beams is analyzed under the local spatial frequency methodology. The maximum nondiffracting propagation distance of aperture-truncated Airy beams is formulated and analyzed based on their local spatial frequency. The validity of the formula is verified by comparing the maximum nondiffracting propagation distance of an aperture-truncated ideal Airy beam, aperture-truncated exponentially decaying Airy beam and exponentially decaying Airy beam. Results show that the formula can be used to evaluate accurately the maximum nondiffracting propagation distance of an aperture-truncated ideal Airy beam. Therefore, it can guide us to select appropriate parameters to generate Airy beams with long nondiffracting propagation distance that have potential application in the fields of laser weapons or optical communications.

  4. Influence of modulation frequency in rubidium cell frequency standards

    Science.gov (United States)

    Audoin, C.; Viennet, J.; Cyr, N.; Vanier, J.

    1983-01-01

    The error signal which is used to control the frequency of the quartz crystal oscillator of a passive rubidium cell frequency standard is considered. The value of the slope of this signal, for an interrogation frequency close to the atomic transition frequency is calculated and measured for various phase (or frequency) modulation waveforms, and for several values of the modulation frequency. A theoretical analysis is made using a model which applies to a system in which the optical pumping rate, the relaxation rates and the RF field are homogeneous. Results are given for sine-wave phase modulation, square-wave frequency modulation and square-wave phase modulation. The influence of the modulation frequency on the slope of the error signal is specified. It is shown that the modulation frequency can be chosen as large as twice the non-saturated full-width at half-maximum without a drastic loss of the sensitivity to an offset of the interrogation frequency from center line, provided that the power saturation factor and the amplitude of modulation are properly adjusted.

  5. Ionizing radiation detection meter systems usability evaluation. Technical memorandum

    International Nuclear Information System (INIS)

    Severs, Y.; Hughes, R.; Tack, D.; Bossi, L.L.M.

    2002-12-01

    In support of the Canadian Forces Nuclear Detection, Identification and Dosimetry project a usability trial of three Ionizing Radiation Detection Meter Systems (IRDMS) was conducted 18-22 June 2001 at Connaught Ranges. The systems evaluated: System 1: ANPDR 77 Operational System with PDR 77 Alpha/Beta probes and GPS (Global Positioning System) Training System; System 2: ADM 300C Operational System with ABP 100 Alpha/Beta probes and GPS Training System, and System 3: RAM R200 Operational System with PA 100M and RG12 Alpha/Beta probes and GPS Training System. Twelve military personnel (Private to Captain) determined compliance with the bid evaluation criteria. The counter-balanced study, based on a Latin square design, was divided into two assessment phases, an operational phase and a training system phase, which rotated three groups (of four participants each) concurrently through each IRDMS. Groups were trained in set-up, maintenance and operation of each bid IRDMS prior to evaluation. The operational evaluation consisted of a test/maintenance stand, an indoor/outdoor operational stand, and an indoor,/outdoor training system stand. Participants rated the utility and usability of each system, by measuring case of use/maintenance under a range of relevant operational and clothing conditions, compatibility with soldier tasks, compatibility with clothing, compatibility with equipment and operational environments, and case of learning (including an assessment of initial and refresher training implications). A 7-point Likert-like acceptability rating scale, which covered a range from completely unacceptable (1) to completely acceptable (7), was used to evaluate the measures. The combined weighted mean scores were 584.3 for System 1 (70 o /b), 682.0 for System 2 (81 %) and 756.9 for System 3 (90%) out of a total possible score of 840. Participants reported mean scores for System 1 between barely unacceptable and borderline for both indoor and outdoor operations. System 2

  6. Knowledge discovery: Extracting usable information from large amounts of data

    International Nuclear Information System (INIS)

    Whiteson, R.

    1998-01-01

    The threat of nuclear weapons proliferation is a problem of world wide concern. Safeguards are the key to nuclear nonproliferation and data is the key to safeguards. The safeguards community has access to a huge and steadily growing volume of data. The advantages of this data rich environment are obvious, there is a great deal of information which can be utilized. The challenge is to effectively apply proven and developing technologies to find and extract usable information from that data. That information must then be assessed and evaluated to produce the knowledge needed for crucial decision making. Efficient and effective analysis of safeguards data will depend on utilizing technologies to interpret the large, heterogeneous data sets that are available from diverse sources. With an order-of-magnitude increase in the amount of data from a wide variety of technical, textual, and historical sources there is a vital need to apply advanced computer technologies to support all-source analysis. There are techniques of data warehousing, data mining, and data analysis that can provide analysts with tools that will expedite their extracting useable information from the huge amounts of data to which they have access. Computerized tools can aid analysts by integrating heterogeneous data, evaluating diverse data streams, automating retrieval of database information, prioritizing inputs, reconciling conflicting data, doing preliminary interpretations, discovering patterns or trends in data, and automating some of the simpler prescreening tasks that are time consuming and tedious. Thus knowledge discovery technologies can provide a foundation of support for the analyst. Rather than spending time sifting through often irrelevant information, analysts could use their specialized skills in a focused, productive fashion. This would allow them to make their analytical judgments with more confidence and spend more of their time doing what they do best

  7. Speed Estimation in Geared Wind Turbines Using the Maximum Correlation Coefficient

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Marhadi, Kun S.; Jensen, Bogi Bech

    2015-01-01

    to overcome the above mentioned issues. The high speed stage shaft angular velocity is calculated based on the maximum correlation coefficient between the 1 st gear mesh frequency of the last gearbox stage and a pure sinus tone of known frequency and phase. The proposed algorithm utilizes vibration signals...

  8. Don't make me think: a common sense approach to Web usability

    National Research Council Canada - National Science Library

    Krug, Steve

    2006-01-01

    .... To ensure that your sites provide that experience, this guide from usability guru Krug distills his years of on-the-job experience into a practical primer on the do's and don'ts of good Web design...

  9. Combinations of Methods for Collaborative Evaluation of the Usability of Interactive Software Systems

    Directory of Open Access Journals (Sweden)

    Andrés Solano

    2016-01-01

    Full Text Available Usability is a fundamental quality characteristic for the success of an interactive system. It is a concept that includes a set of metrics and methods in order to obtain easy-to-learn and easy-to-use systems. Usability Evaluation Methods, UEM, are quite diverse; their application depends on variables such as costs, time availability, and human resources. A large number of UEM can be employed to assess interactive software systems, but questions arise when deciding which method and/or combination of methods gives more (relevant information. We propose Collaborative Usability Evaluation Methods, CUEM, following the principles defined by the Collaboration Engineering. This paper analyzes a set of CUEM conducted on different interactive software systems. It proposes combinations of CUEM that provide more complete and comprehensive information about the usability of interactive software systems than those evaluation methods conducted independently.

  10. Usability testing of e-learning: an approach incorporating co-discovery and think-aloud

    CSIR Research Space (South Africa)

    Adebesin, TF

    2009-06-01

    Full Text Available Computer applications developed to support learning in the cognitive domains are quite different from commercial transaction processing applications. The unique nature of such applications calls for different methods for evaluating their usability...

  11. Educational Modelling Language and Learning Design: new challenges for instructional re-usability and personalized learning

    NARCIS (Netherlands)

    Hummel, Hans; Manderveld, Jocelyn; Tattersall, Colin; Koper, Rob

    2003-01-01

    Published: Hummel, H. G. K., Manderveld, J. M., Tattersall, C.,& Koper, E. J. R. (2004). Educational Modelling Language: new challenges for instructional re-usability and personalized learning. International Journal of Learning Technology, 1, 1, 110-111.

  12. Usability study of a novel, self-lighted, disposable speculum: military applications.

    Science.gov (United States)

    Jones, Christina L; Gruber, Daniel D; Warner, William; Buller, Jerome L

    2013-04-01

    Data collected from a postutilization questionnaire were used to evaluate the usability of the OfficeSPEC disposable vaginal speculum, specifically the effectiveness, efficiency, and acceptability, in clinical, hospital, and austere environments. Usability data analysis showed the OfficeSPEC speculum had an effectiveness rating of 4.6/5, efficiency rating of 4.5/5, and acceptability rating of 4.6/5; overall usability in deployed environments was favorable. The overall rankings were 3.4 for plastic, 4.2 for metal (p disposable speculum as a reasonable alternative with yearly cost of $129,200, compared to traditional metal ($209,100) and plastic ($319,175). By evaluating the OfficeSPEC speculum within a usability framework, it proved to be practical, viable alternative in all environments, particularly in the forward deployed environment. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.

  13. Investigation into the usability of MSDL in South African C2 tactical simulations

    CSIR Research Space (South Africa)

    Le Roux, WH

    2007-06-01

    Full Text Available The applicability and usability of the Military Simulation Definition Language (MSDL) is investigated in context of the South African air Defence simulation community. A constructive, tactical command and control simulation environment used...

  14. WEB USABILITY OF PUBLIC ORGANIZATION WEBSITES: The Case of Indonesian Ministry Websites

    Directory of Open Access Journals (Sweden)

    Ali Rokhman

    2012-08-01

    Full Text Available As a consequence of the development of Information and Communication Technologies (ICT, nowadays almost all governments around the world, included Indonesian government have official websites to provide information and services for their citizen. In the second period of President Susilo Bambang Yudhoyono administration has thirty two ministries and each ministries have an official website. However implementation of the ministry websites have not been measured yet on usability aspect. The objective of this research is to examine the usability of ministry websites of Indonesian Government. Eleven websites was taken as sample in this study. Respondents are 128 Internet users who have competency for assessing web usability. Usability of websites were measured by several indicators were adapted from E-Government Toolkit for Developing Countries that was prepared by the National Informatics Centre and UNESCO. The main indicators consist of navigation architecture, layout design, and content.

  15. Usability of geographic information -- factors identified from qualitative analysis of task-focused user interviews.

    Science.gov (United States)

    Harding, Jenny

    2013-11-01

    Understanding user needs for geographic information and the factors which influence the usability of such information in diverse user contexts is an essential part of user centred development of information products. There is relatively little existing research focused on the design and usability of information products in general. This paper presents a research approach based on semi structured interviews with people working with geographic information on a day to day basis, to establish a reference base of qualitative data on user needs for geographic information with respect to context of use. From this reference data nine key categories of geographic information usability are identified and discussed in the context of limited existing research concerned with geographic information usability. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  16. web portal usability among na case study of univer se study of ...

    African Journals Online (AJOL)

    User

    2014-04-02

    Apr 2, 2014 ... ABSTRACT. The web portal technology by Nigerian universitie university ... Portal Usability Success (WEBPUS) Model .... to deliver education to students [4]. Despite ..... and Mobile Research Lab (ITML) and group members.

  17. Don't make me think: a common sense approach to Web usability

    National Research Council Canada - National Science Library

    Krug, Steve

    2006-01-01

    .... The second edition of this classic adds three new chapters that explain why people really leave Web sites, how to make sites usable and accessible, and the art of surviving executive design whims...

  18. Review of Spatial-Database System Usability: Recommendations for the ADDNS Project

    National Research Council Canada - National Science Library

    Abdalla, R. M; Niall, K. K

    2007-01-01

    ...) and three-dimensional (3D) visualizations. This report presents an overview of the basic concepts of GIS and spatial databases, provides an analytical usability evaluation and critically analyses different spatial- database applications...

  19. A Benchmark Usability Study of the Tactical Decision Making Under Stress Decision Support System

    National Research Council Canada - National Science Library

    Schmorrow, Dylan

    1998-01-01

    This study evaluates the usability of a U.S. Navy Decision Support System (DSS). The DSS was developed to enhance the performance of tactical decision makers within a Navy Combat Information Center...

  20. Human Machine Interface and Usability Issues: Exploring a Preliminary Mission Management System Evaluation Methodology

    National Research Council Canada - National Science Library

    Kardos, Monique

    2001-01-01

    ...) concept demonstrator test during June 2000. The questionnaire was designed to examine usability and interface issues relating to the design of the systems or tools, and to provide suggestions for future iterations of the system...